Fish oil: The natural triglyceride form is better

If you have a choice, the triglyceride form of fish oil is preferable. The triglyceride form, i.e., 3 omega-3 fatty acids on a glycerol "backbone," is the form found in the body of fish that protects them from cold temperatures (i.e., they remain liquid at low ambient temperatures).

Most fish oils on the market are the ethyl ester form. This means that the omega-3 fatty acids have been removed from the glycerol backbone; the fatty acids are then reacted with ethanol to form the ethyl ester.

If the form is not specified on your fish oil bottle, it is likely ethyl ester, since the triglyceride form is more costly to process and most manufacturers therefore boast about it. Also, prescription Lovaza--nearly 20 times more costly than the most expensive fish oil triglyceride liquid on a milligram for milligram basis--is the ethyl ester form. That's not even factoring in reduced absorption of ethyl esters compared to triglyceride forms. Remember: FDA approval is not necessarily a stamp of superiority. It just means somebody had the money and ambition to pursue FDA approval. Period.

Taking any kind of fish oil, provided it is not overly oxidized (and thereby yields a smelly fish odor), is better than taking none at all. All fish oil will reduce triglycerides, accelerate clearance of postprandial (after-eating) lipoprotein byproducts of a meal (via activation of lipoprotein lipase), enhance endothelial responsiveness, reduce small LDL particles, and provide a physical stabilizing effect on atherosclerotic plaque.

But if you desire enhanced absorption and potentially lower dose to achieve equivalent RBC omega-3 levels, then triglyceride forms are better.

Here are cut-and-pasted abstracts of two of the studies comparing forms of fish oil.

Bioavailability of marine n-3 fatty acid formulations.

Dyerberg J, Madsen P, Moller JM et al. 
Department of Human Nutrition, Faculty of Life Sciences, University of Copenhagen, Copenhagen, Denmark.

Abstract

The use of marine n-3 polyunsaturated fatty acids (n-3 PUFA) as supplements has prompted the development of concentrated formulations to overcome compliance problems. The present study compares three concentrated preparations - ethyl esters, free fatty acids and re-esterified triglycerides - with placebo oil in a double-blinded design, and with fish body oil and cod liver oil in single-blinded arms. Seventy-two volunteers were given approximately 3.3g of eicosapentaenoic acid (EPA) plus docosahexaenoic acid (DHA) daily for 2 weeks. Increases in absolute amounts of EPA and DHA in fasting serum triglycerides, cholesterol esters and phospholipids were examined. Bioavailability of EPA+DHA from re-esterified triglycerides was superior (124%) compared with natural fish oil, whereas the bioavailability from ethyl esters was inferior (73%). Free fatty acid bioavailability (91%) did not differ significantly from natural triglycerides. The stereochemistry of fatty acid in acylglycerols did not influence the bioavailability of EPA and DHA.
(Full text of the Dyerberg et al study made available at the Nordic Naturals website here.)



Eur J Clin Nutr 2010 Nov 10. 

Enhanced increase of omega-3 index in response to long-term n-3 fatty acid supplementation from triacylglycerides versus ethyl esters.

Neubronner J, Schuchardt JP, Kressel G et al. 
Institute of Food Science and Human Nutrition, Leibniz Universität Hannover, Am Kleinen Felde 30, Hannover, Germany.

Abstract

There is a debate currently about whether different chemical forms of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are absorbed in an identical way. The objective of this study was to investigate the response of the omega-3 index, the percentage of EPA+DHA in red blood cell membranes, to supplementation with two different omega-3 fatty acid (n-3 FA) formulations in humans. The study was conducted as a double-blinded placebo-controlled trial. A total of 150 volunteers was randomly assigned to one of the three groups: (1) fish oil concentrate with EPA+DHA (1.01?g+0.67?g) given as reesterified triacylglycerides (rTAG group); (2) corn oil (placebo group) or (3) fish oil concentrate with EPA+DHA (1.01?g+0.67?g) given as ethyl ester (EE group). Volunteers consumed four gelatine-coated soft capsules daily over a period of six months. The omega-3 index was determined at baseline (t(0)) after three months (t(3)) and at the end of the intervention period (t(6)). The omega-3 index increased significantly in both groups treated with n-3 FAs from baseline to t(3) and t(6) (P < 0.001). The omega-3 index increased to a greater extent in the rTAG group than in the EE group (t(3): 186 versus 161% (P < 0.001); t(6): 197 versus 171% (P < 0.01)). Conclusion: A six-month supplementation of identical doses of EPA+DHA led to a faster and higher increase in the omega-3 index when consumed as triacylglycerides than when consumed as ethyl esters.

Diarrhea, asthma, arthritis--What is your wheat re-exposure syndrome?

Have you experienced a wheat re-exposure syndrome?

As I recently discussed, gastrointestinal distress--cramps, gas, diarrhea--is the most common "syndrome" that results from re-exposure to wheat after a period of elimination.

Others experience asthma, sinus congestion and infections, mental "fogginess" and difficulty concentrating, or joint pains and/or overt swelling.

Still others say there is no such thing.

Let's take a poll and find out what readers say.

Marathoners, triathletes, and heart disease

Curious thing: People with lipoprotein(a) gravitate towards elite levels of exercise.

I tell my lipoprotein(a) patients that, if they want to see a lot of other people with lipoprotein(a), go to a marathon or triathlon.

This effect applies more to males than to females, just as the fascination with numbers seems to be confined to men, too. That's why I've posted in past about the "prototypical" lipoprotein(a) male.

I believe this is a big part, perhaps the only, reason why there seems to be a modest increased risk for cardiovascular events despite high exercise levels in marathoners. It has nothing to do with the exercise itself; it has to do with the kind of people who choose to exercise at this level.

The best fish oil

The best fish oils available are the liquid forms. Contrary to many people's expectations, the best liquid fish oils have no fishy odor or taste.

I use a lot of liquid fish oils because of the higher doses we use in the Track Your Plaque program, as well as our strategy of high-dose fish oil to reduce lipoprotein(a). Women, in particular, don't like taking the oodles of capsules required to achieve the higher doses we need. So the ladies really like the liquid forms.

The best liquid fish oils are non-fishy, highly-concentrated, and come in the better absorbed triglyceride form. Many capsules, including prescription Lovaza, are the less well-absorbed ethyl ester form. Several studies, such as this one, have now demonstrated that the naturally-occurring triglyceride form yields higher blood (RBC) levels of omega-3 fatty acids, likely due to more efficient digestion via pancreatic lipase.

While there are many good forms of fish oil and only a few bad, these are the best of the best:

Pharmax
The Pharmax Finest Pure Fish Oil with Essential Oil of Orange contains 1800 mg EPA + DHA per teaspoon. This is the preparation I've been taking.

Nordic Naturals
The Nordic Naturals lemon-flavored ProOmega Liquid contains 2752 mg EPA + DHA per teaspoon, the most concentrated of any fish oil I've seen.

(This list is not exclusive. These are just two brands I've used extensively with good results.)

These highly-concentrated, triglyceride forms are more expensive, due to their concentrated nature. 1 teaspoon Pharmax fish oil, for example, provides an equivalent quantity of omega-3 fatty acids as 6 standard fish oil capsules on a milligram for milligram basis, but more like 8 to 9 capsules when absorption efficiency is factored in. The triglyceride form is also more laborious to manufacture. On our Track Your Plaque Marketplace, our Pharmax 500 ml runs $58.95 list. (500 ml provides 100 teaspoons or 600-capsule equivalent.)

Note that, minus the protection of the capsule, liquid fish oils will oxidize if not refrigerated. So be sure to keep your liquid fish oil in the fridge.

What do Salmonella, E coli, and bread have in common?

Say you happen to eat some chicken fingers contaminated with bacteria because the 19-year old kid behind the counter failed to wash his hands after using the toilet, or because the kitchen is poorly managed with unwashed counters and cutting boards, or because the food is undercooked. You get a bout of diarrhea and cramps, along with a desire to banish chicken from your life.

Here's yet another odd wheat phenomenon: About 30% of people who eliminate wheat from their lives experience an acute food poisoning-like effect on re-exposure. You've been wheat-free for, say, 6 months. You've lost 25 lbs from your wheat belly, you've regained energy, joints feel better. You go to an office party where they're serving some really yummy looking bruschetta. Surely a couple won't hurt! Within a hour, you're getting that awful rumbling and unease that precede the explosion.

The majority of people who experience a wheat re-exposure syndrome will have diarrhea and cramps that can last from hours to days, similar to food poisoning. (Why? Why would a common food trigger a food poisoning-like effect? It happens too fast to attribute to inflammation.) Others experience asthma attacks, joint pains that last 48 hours to a week, mental fogginess, emotional distress, even rage (in males).

Wheat re-exposure in the susceptible provides a tidy demonstration of the effects of this peculiar product of genetic research. So if you are wheat-free but entertain an occasional indulgence, don't be surprised if you have to make a beeline to the toilet.

The world of intermediate carbohydrates

There are clear-cut bad carbohydrates: wheat, oats, cornstarch, and sucrose. (Fructose, too, but in a class of bad all its own.)

Wheat: The worst. Not only does wheat flour increase blood sugar higher than nearly all other carbohydrates, it invites celiac disease, neurologic impairment, mental and emotional effects, addictive (i.e., exorphin) effects, asthma, irritable bowel syndrome, acid reflux, sleepiness, sleep disruption, arthritis . . . just to name a few.

Oats: Yeah, yeah, I know: "Lowers cholesterol." But nobody told you that oats, including slow-cooked oatmeal, causes blood sugar to skyrocket.

Cornstarch: Like wheat, cornstarch flagrantly increases blood sugar.It also stimulates appetite. That's why food manufacturers put it in everything from soups to frozen dinners.

Sucrose: Not only does sucrose create a desire for more food, it is also 50% fructose, the peculiar sugar that makes us fat, increases small LDL particles, increases triglycerides, slows the metabolism of other foods, encourages diabetes, and causes more glycation than any other sugar.

But there are a large world of "other" natural carbohydrates that don't fall into the really bad category. This includes starchy beans like black, kidney, and pinto; rices such as white, brown, and wild; potatoes, including white, red, sweet, and yams; and fruits. It includes "alternative" grains like quinoa, spelt, triticale, amaranth, and barley.

For lack of a better term, I call these "intermediate" carbohydrates. They are not as bad as wheat, etc., but nor are they good. They will still increase blood glucose, small LDL, triglycerides, etc., just not as much as the worst carbohydrates.

The difference is relative. Say we compare the one-hour blood glucose effects of 1 cup of wheat flour product vs. one cup of quinoa. Typical blood sugar after wheat product: 180 mg/dl. Typical blood sugar after quinoa: 160 mg/dl--better but still pretty bad.

Some people are so carb-sensitive that they should avoid even these so-called intermediate carbohydrates. Others can have small indulgences, e.g., 1/2 cup, and not generate high blood sugars.

Heroin, Oxycontin, and a whole wheat bagel

For a substantial proportion of people who remove wheat from their diet, there is a distinct and unpleasant withdrawal syndrome. Here are the comments of Heart Scan Blog reader, Scott, from Texas:

Hello Dr. Davis,

I've been experimenting with diet, converging upon a Paleo type diet, but I keep running into problems. I have isolated the problem to cutting out wheat.

Sugar, rice, fruit, corn, potatoes, etc. are relatively ok to add or remove from the diet, but cutting out wheat in particular brings on a moderate headache with heavy fatigue all day long. This resembles the wheat withdrawal symptoms I found on your blog. As I write this, I'm on day 8 of wheat-free. I consume a fair variety of meat and veggies each day with a moderate amount of white rice for carbs. Perhaps a bowl of corn flakes with milk and half a bar of dark chocolate a day. I've learned from experience over the past 5 months or so that none of these foods affect the withdrawal. It's purely wheat.

My question is, what is the range of times for withdrawal symptoms that you've heard from different people? Has there been anyone who never recovered from the wheat withdrawal symptoms even after many months?

It's very tough to get work done like this, and even though my body and head feel much healthier in general, my sinuses have cleared, don't have to take a big nap after I eat, etc., I don't want to go down a path where this is the way things are going to be forever. 



People who have never experienced wheat withdrawal pooh-pooh the effect. But, for about 30% of people, wheat withdrawal is a real, palpable, and sometimes incapacitating experience.

Beyond removing an exceptionally digestible carbohydrate that yields blood sugar rises higher than nearly any other known food (due to the unique amylopectin structure of wheat-derived carbohydrate), wheat withdrawal is a form of opiate withdrawal, somewhat like stopping heroin, Oxycontin, and other opiates. Stop eating whole wheat toast for breakfast, whole grain sandwiches for lunch, or whole grain pasta for dinner, and the flow of exorphins, i.e., exogenous morphine-like compounds, stops. You experience dysphoria (sadness, unhappiness), mental "fog," inability to concentrate, fatigue, and decreased capacity to exercise. It is milder than withdrawal from prescription opiates. Unlike withdrawal from more powerful opiates like heroine, there are, thankfully, no seizures or hallucinations. There are also no deaths.

In my experience, most people get through with wheat withdrawal in about 5 days. An occasional person will struggle for as long as 4 weeks. Thankfully for Scott, I've never seen it last longer than 4 weeks. (Interestingly, people who survive the withdrawal syndrome are often prone to a peculiar re-exposure phenomenon that I will discuss in future, i.e., they get sick upon re-exposure.)

The modern dwarf mutant variant of Triticum aestivum (that our USDA urges us to eat more of) contains greater proportions of gluten proteins compared to wheat pre-1970; glutens are the source of wheat-derived exorphins.

Incidentally, a drug company should be releasing a drug in the next year that will contain naltrexone, an oral opiate blocking drug, for a weight loss indication. They claim it is a blocker of the "mesolimbic reward system." I say it's a blocker of wheat exorphins.

The five most powerful heart disease prevention strategies

You've seen such lists before: 5 steps to prevent heart disease or some such thing. These lists usually say things like "cut your saturated fat," eat a "balanced diet" (whatever the heck that means), exercise, and don't smoke.

I would offer a different list. You already know that smoking is a supremely idiotic habit, so I won't repeat that. Here are the 5 most important strategies I know of that help you prevent heart disease and heart attack:

1) Eliminate wheat from the diet--Provided you don't do something stupid, like allow M&M's, Coca Cola, and corn chips to dominate your diet, elimination of wheat is an enormously effective means to reduce small LDL particles, reduce triglycerides, increase HDL, reduce inflammatory measures like c-reactive protein, lose weight (inflammation-driving visceral fat), reduce blood sugar, and reduce blood pressure. I know of no other single dietary strategy that packs as much punch. This has become even more true over the past 20 years, ever since the dwarf variant of modern wheat has come to dominate.

2) Achieve a desirable 25-hydroxy vitamin D level--Contrary to the inane comments of the Institute of Medicine, vitamin D supplementation increases HDL, reduces small LDL, normalizes insulin and reduces blood sugar, reduces blood pressure, and exerts potent anti-inflammatory effects on c-reactive protein, matrix metalloproteinase, and other inflammmatory mediators. While we also have drugs that mimic some of these effects, vitamin D does so without side-effects.

3) Supplement omega-3 fatty acids from fish oil--Omega-3 fatty acids reduce triglycerides, accelerate postprandial (after-meal) clearance of lipoprotein byproducts like chylomicron remnants, and have a physical stabilizing effect on atherosclerotic plaque.

4) Normalize thyroid function--Start with obtaining sufficient iodine. Iodine is not optional; it is an essential trace mineral to maintain normal thyroid function, protect the thyroid from the hundreds of thyroid disrupters in our environment (e.g., perchlorates from fertilizer residues in produce), as well as other functions such as anti-bacterial effects. Thyroid dysfunction is epidemic; correction of subtle degrees of hypothyroidism reduces LDL, reduces triglycerides, reduces small LDL, facilitates weight loss, reduces blood pressure, normalizes endothelial responses, and reduces oxidized LDL particles.

5) Make exercise fun--Not just exercise for the sake of exercise, but physical activity or exercise for the sake of having a good time. It's the difference between resigning yourself to 30 minutes of torture and boredom on the treadmill versus engaging in an activity you enjoy and look forward to: go dancing, walk with a friend, organize a paintball tournament outdoors, Zumba class, plant a new garden, etc. It's a distinction that spells the difference between finding every excuse not to do it, compared to making time for it because you enjoy it.

Note what is not on the list: cut your fat, eat more "healthy whole grains," take a cholesterol drug, take aspirin. That's the list you'd follow if you feel your hospital needs your $100,000 contribution, otherwise known as coronary bypass surgery.

Topping up your vitamin D tank

Now that my vitamin D replacement experience dates back nearly 5 years, I've been witnessing an unusual phenomenon:

The longer you take vitamin D, the less you need.

Let me explain. You take 10,000 units D3 in gelcap form. 25-hydroxy vitamin D levels, checked every 6 months, have remained consistently between 60 and 70 ng/ml. Three years into your vitamin D experience and 25-hydroxy vitamin D level rises to 98 ng/ml--an apparent need for less vitamin D.

So we cut your intake from 10,000 units per day to 8000 units per day. Another 25-hydroxy vitamin D level 6 months later: 94 ng/ml. We cut dose again to 6000 units, followed by another 25-hydroxy vitamin D level of 66 ng/ml.

This has now happened in approximately 20% of the people who have been taking vitamin D for 3 or more years. I know of no formal analysis of this effect, what I call the "topping up" phenomenon. Reasoned simply, it seems to me that, once your vitamin D "tank" is topped up (i.e., tissue stores have been replenished), it requires less to keep it full.

No one has experienced any adverse consequence of this topping up effect though it has potential for some people to develop toxic levels if 25-hydroxy vitamin D levels are not monitored long-term. In my office, I measure 25-hydroxy vitamin D levels every 6 months.

It means that long-term monitoring of 25-hydroxy vitamin D is crucial to maintain favorable and safe levels.

Thirteen catheterizations later

When I first met her, Janet couldn't stop sobbing. She'd just been through her 10th heart catheterization in two years.

It started with chest pains at age 56, prompting her first heart catheterization that uncovered severe atherosclerotic blockages in all three coronary arteries. Her cardiologist advised a bypass operation.

Six months after the bypass operation, Janet was back with more chest pains, just as bad as before. Another heart catherization showed that two of the three bypass grafts had failed. The third bypass graft contained a severe blockage that required a stent, along with multiple stents in the two now unbypassed arteries.

In the ensuing 18 months, Janet returned for 8 additional catheterizations, each time leaving the hospital with one or more stents.

Janet's doctor was puzzled as to why her disease was progressing so aggressively despite Lipitor and the low-fat diet provided by the hospital dietitian. So he had Janet undergo lipoprotein testing (NMR):

LDL particle number: 3363 nmol/L
Small LDL particle number: 2865 nmol/L
HDL cholesterol: 32 mg/dl
Triglycerides: 344 mg/dl
Fasting blood glucose 118 mg/dl
HbA1c 5.8%

Unfortunately, Janet's doctor didn't understand what these values meant. He pretty much threw his arms up in frustration. That's when I met Janet.

From her lipoprotein panel and other values, it was clear to me that Janet was miserably carbohydrate-sensitive and carbohydrate-indulgent, as demonstrated by the extravagant quantity (2865 nmol/L) and proportion (2865/3363, or 85%) of small LDL, the form of LDL particles created by carbohydrate exposure. Janet struggled with depression over the years and had been using carbohydrate foods as "comfort" foods, often resorting to cookies, pies, cakes, breads, and other wheat-containing foods for emotional solace.

It took a bit of persuasion to convince Janet that it was low-fat, "healthy whole grains," as well as comfort foods, that had led her down this path. I also helped Janet correct her severe vitamin D deficiency, mild thyroid dysfunction, and lack of omega-3 fatty acids.

Since meeting Janet and instituting her new prevention program, she has undergone three additional catheterizations (performed by another cardiologist), all performed for chest pain symptoms that struck during periods of emotional stress. All showed . . . no significant blockage. (Apparently, the repeated "need" for stents triggered a Pavlovian response: chest pain = "need" for yet more stents.)

In short, correction of the causes of coronary atherosclerotic plaque--small LDL, vitamin D deficiency, omega-3 fatty acid deficiency, and thyroid dysfunction--and Janet's disease essentially ground to a halt.

Imagine, instead, that Janet had undergone 1) a heart scan to identify hidden coronary plaque 5-10 years before her first heart procedure, then 2) corrected the causes before they triggered symptoms and posed danger. She might have been spared an extraordinary amount of life crises, hospital procedures, expense (nearly $1 million), and emotional suffering.

Triglyceride and chylomicron "stacking"

Continuing the comments started in Grazing is for cattle, here's an interesting study from the Oxford Center for Diabetes, Endocrinology and Metabolism.

Volunteers were fed a test meal breakfast of Rice Krispies, a banana, and a chocolate milkshake (76.4 grams carbohydrates, 51.9 grams fat, 12.2 grams protein). Lunch was served 5 hours later and consisted of a cheese sandwich and a second chocolate milkshake 43.4 grams carbohydrates, 49.6 grams fat, 24.0 grams protein). Frequent blood samples were then assessed over the day. (Don't try this at home: These are obviously very dangerous foods!)

Here's the pattern of triglycerides that was observed (1st dotted vertical line = breakfast, 2nd dotted vertical line = lunch):



Note that triglycerides only begin to decline 3-4 hours after breakfast, only to peak higher after lunch.


Here's the pattern observed for chylomicrons, the "granddaddy" of lipoproteins that derives from intestinal absorption of fatty acids:



Both graphs from Heath RB et al Am J Phyiol Endocrinol Metab 2006.


With chylomicrons, note a similar pattern to triglycerides: Chylomicrons begin to decline at 3-4 hours, only to peak higher after lunch.

This is the first study to examine the effect of sequential meals on such postprandial (after-eating) patterns. But it makes the graphic point that, if insufficient time is permitted between meals, both triglycerides and chylomicrons will "stack" themselves higher and higher. (Chylomicrons are subjected to processing by the enzyme, lipoprotein lipase, to form highly atherogenic, or plaque-causing, chylomicron remnants.)

While not examined in this study, my bet is that "grazing," i.e., eating small meals or snacks frequently, is an extreme instance of triglyceride, chylomicron, and chylomicron remnant stacking. That can only lead to one thing: accelerated heart and vascular plaque.

What is a healthy vitamin D blood level?

When measuring blood levels of vitamin D (as 25-hydroxy vitamin D), what constitutes a desirable level?

There's no study that directly examines this question, no study that enrolled thousands of people and assigned a placebo group and groups receiving escalating doses of vitamin D and/or achieved higher levels of vitamin D, then observed for development of cancer, diabetes, depression, heart disease, multiple sclerosis, osteoporosis, osteoarthritis, etc. Such a study would requires many thousands of participants (particularly to observe cancer and multiple sclerosis incidence), many years of observation, and many tens of millions of dollars. Nope, only a drug company could afford such costs.

So we have to piece together various observations and extrapolate what we believe to be the ideal level of vitamin D. Epidemiologic observations in several cancers (breast, colon, prostate, and bladder) suggest that a 25-hydroxy vitamin D level of 30 ng/ml or higher is desirable (with less cancer incidence above this level). Other data suggest a level of 52 ng/ml or greater is desirable. Unfortunately, much cancer research looked at intake of vitamin D from food and supplement sources, rather than actual blood levels. We also have to factor in the great individual variation in vitamin D metabolism, with a single dose yielding variable blood levels (as much as a 10-fold difference). There's also the variation introduced by vitamin D-receptor variation (genetic polymorphisms).

A new study using vitamin D administration helps chart the desirable levels of vitamin D.

Vitamin D supplementation reduces insulin resistance in South Asian women living in New Zealand who are insulin resistant and vitamin D deficient - a randomised, placebo-controlled trial.

In this New Zealand study, 42 women (23 to 68 years old) were given 4000 units vitamin D, 39 women given placebo. Median 25-hydroxy vitamin D levels increased from 21 nmol/L (8.4 ng/ml) to 75 nmol/L (30 ng/ml). Both HOMA (a measure of insulin sensitivity) and fasting insulin levels improved, with greatest improvement seen at 25-hydroxy vitamin D levels of 80-119 nmol/L (32-47.6 ng/ml) or greater.

We also know that a vacation on a Caribbean beach in a bathing suit will increase vitamin D blood levels to the 80-110 ng/ml range without ill-effect (at least in young people who maintain the capacity to activate vitamin D in the skin, a phenomenon that declines as we age).

So do we really know the truly ideal level of vitamin D to achieve? I believe that, given the above observations, it is reasonable to extrapolate that the ideal vitamin D blood level likely lies somewhere above 50 ng/ml. We also know that vitamin D toxicity (i.e., hypercalcemia) is virtually unheard of until vitamin D blood levels approach 150 ng/ml, and even then is inconsistent. The health benefits of vitamin D supplementation are so tremendous, that I am not willing to wait for the prospective data to explore this question fully. For now, I aim for a blood level of vitamin D of 60-70 ng/ml (150-175 nmol/L).

Grazing is for cattle

Many dietitians and nutritionists advise many people today to "graze," i.e., to eat small snacks every couple of hours. They argue that it blocks the drop in insulin and blood sugar that can trigger greater appetite and claim it can facilitate weight loss.



This is an absurd notion. Humans are not meant to graze. Humans are meant to find a wild boar or other animal, kill it, gorge on the meat, organs, and fat, then revert to berries, roots, leaves, and other foraged foods until the next kill. A human living in the wild does not have a cupboard or refrigerator full of ready-to-eat snacks to graze on.

The several hours after a meal is the most dangerous for creating coronary atherosclerotic plaque, i.e., the post-prandial period. In other words, eat dinner and, for the next 6-12 hours, your intestinal tract degrades the food; food byproducts are absorbed into the blood or lymph system. The blood is literally flooded with the byproducts of your meal.

Postprandial abnormalities are emerging to be a potent, and much underappreciated, means of causing heart disease and atherosclerosis in other vascular territories (especially carotid arteries and thoracic aorta).

Not eating--i.e., the fasting state--for extended periods is good for you. Encouraging people to graze amplifies atherosclerotic risk, since it creates an abnormal prolonged postprandial state.

The disastrous results of a low-fat diet

Rob was never that committed to following the program in the first place.

I met Rob because of a modest heart scan score and consultation for a cholesterol abnormality. Rob had been cycled through all the statin agents by his primary care physician, all of which resulted in terrible muscle aches that he found intolerable.

I started out, as usual, characterizing his cholesterol abnormality with lipoprotein testing (NMR):

LDL particle number 1489 nmol/L
LDL cholesterol (Friedewald calculation) 143 mg/dl
Small LDL 52% of total LDL
HDL 50 mg/dl
Triglycerides 82 mg/dl

(LDL particle number is the emerging gold standard for LDL quantification, superior to calculated or Friedewald LDL cholesterol for prediction of cardiovascular events.)

Rob is a busy guy. After only a couple of brief visits, life and work got in the way and Rob let his attentions drift away from heart health. Since the information I provided made little impact on his thinking, he reverted to the low-fat diet his primary care doctor had originally prescribed and that he read about in magazines and food packages. He also ran out of the basic supplements I had advised, including fish oil and vitamin D, and just never restarted them.

A couple of years passed and Rob decided that just poking around on his own might not cut it. So he came back to the office. We repeated his NMR lipoprotein analysis:

LDL particle number 2699 nmol/L
LDL cholesterol (Friedewald calculation) 229 mg/dl
Small LDL 81% of total LDL
HDL 53 mg/dl
Triglycerides 78 mg/dl


Two years of a low-fat diet had caused Rob's LDL particle number to skyrocket by 81%, nearly all due to an explosion of small LDL. Recall that small LDL is more susceptible to oxidation, more inflammation-provoking, more adhesive--the form of LDL particles most likely to cause heart disease.

Also, note that, despite the enormous increase in small LDL, HDL and triglycerides remained favorable. This counters the popular rule-of-thumb offered by some that small LDL is not present when HDL is "normal."

Low-fat diets as commonly practiced are enormously destructive. In Rob's case, a low-fat diet caused both calculated Friedewald LDL as well as LDL particle number to increase dramatically. In many other people, low-fat diets increase calculated Friedewald LDL modestly or not at all, but cause the more accurate LDL particle number to increase significantly, all due to small LDL.

I'm happy to say that, once Rob witnessed how far wrong he could go on the wrong program, he's back on Track. (Sorry, pun intended.) He has resumed his supplements and eliminated the food triggers of small LDL--wheat, cornstarch, and sugars.

Dr. David Grimes reminds us of vitamin D

In response to the Heart Scan Blog post, Fish oil makes you happy: Psychological distress and omega-3 index, Dr. David Grimes offered the following argument.

Dr. Grimes is a physician in northwest England at the Blackburn Royal Infirmary, Lancashire. He is author of the wonderfully cheeky 2006 Lancet editorial, Are statins analogues of vitamin D?, questioning whether the benefits of statin drugs simply work by way of increased vitamin D blood levels.


There is a fashionable interest in Omega-3 fatty acids, and these become equated with fish oil.

But fish oil is much more. Plankton synthesise the related squalene (shark oil) which, in turn, is converted into 7-dehydrocholesterol (7-DHC). The sun now comes into play and it converts 7-DHC into vitamin D (a physico-chemical process).

Small fish eat plankton, large fish eat small fish, and we eat large fish. So vitamin D passes through the food chain.

This has been a vital source of vitamin D for the the Inuits and also for the Scots and other dwellers of northwest Europe. (Edinburgh is on the same latitude as Hudson Bay and Alaska, further north than anywhere in China). In these locations there is not adequate sunlight energy to guarantee synthesis of adequate amounts of vitamin D, again by the action of sunlight on 7-DHC in the skin.

When the Scots moved from coastal fishing villages to industrial cities such as Glasgow, they became seriously deficient in vitamin D, and so the emergence of rickets. This was followed by a variety of other diseases resulting from vitamin D deficiency: tuberculosis, dental decay, coronary heart disease, and even multiple sclerosis and depression (the Glasgow syndrome).

And so it was with the Inuits. When their diet changed from fish for breakfast, fish for lunch, fish for dinner, they became deficient of vitamin D and they developed diseases characteristic of industrial cities, where there is indoor work for long hours, indoor activities, and atmospheric pollution.

It is the vitamin D component of fish and fish oils that is important.

I recently saw an elderly lady from Bangladesh living in northwest England. I would have expected her to have a very low blood level of vitamin D, as her exposure to the sun was minimal. However the blood level was 47ng/ml, not 4 as expected. She eats oily fish from Bangladesh every day, showing its value as a source of vitamin D with subsequent good health. I expect her blood levels of omega-3 fatty acids would also be high.

But it is unfashionable vitamin D that is important, not fashionable omega-3.

David Grimes
www.vitamindandcholesterol.com


Excellent point. The health effects of omega-3 and vitamin D are intimately intertwined when examining populations that consume fish.

In this study of Inuits, it is indeed impossible to dissect out how much psychological distress was due to reduced vitamin D, how much due to reduced omega-3s. My bet is that it's both. Thankfully, we also have data examining the use of pure omega-3 fatty acids in capsule (not intact fish) form, including studies like GISSI Prevenzione.

Nonetheless, Dr. Grimes reminds us that both vitamin D and omega-3 fatty acids from fish oil play crucial roles in mental health and other aspects of health, and that it's the combination that may account for the extravagant health effects previously ascribed only to omega-3s.

Why does fish oil reduce triglycerides?

Beyond its ability to slash risk for cardiovascular events, omega-3 fatty acids from fish oil also reduce triglycerides.

There's no remaining question that omega-3s do this quite effectively. After all, the FDA approved prescription fish oil, Lovaza, to treat a condition called familial hypertriglyceridemia, an inherited condition in which very high triglycerides in the 100s or 1000s of milligrams typically develop.

The omega-3 fraction of fatty acids are unique for their triglyceride-reducing property. No other fraction of fatty acids, such as omega-6 or saturated, can match the triglyceride-reducing effect of omega-3s.

But why does fish oil reduce triglycerides?

First of all, what are triglycerides? As their name suggests, triglycerides consist of three ("tri-") fatty acids lined up along a glycerol (sugar) "backbone." Triglycerides are the form in which most fatty acids occur in the bloodstream, liver, and other organs. (Fatty acids, like omega-3, omega-6, mono- or polyunsaturated, or saturated, rarely occur as free fatty acids unbound to glycerol.) In various lipoproteins in the blood, like LDL, VLDL, and HDL, fatty acids occur as triglycerides.

Of all lipoproteins, chylomicrons (the large particle formed through intestinal absorption of fatty acids and transported to the liver via the lymph system) and VLDL (very low-density lipoprotein, very low-density because they are mostly fat and little protein) particles are richest in triglycerides. Thus, we would expect that omega-3s exert their triglyceride-reducing effect via reductions in either chylomicrons or VLDL.

Indeed, that seems to be the case. The emerging evidence suggests that omega-3 fatty acids from fish oil reduce triglycerides through:

--Reduced VLDL production by the liver (Harris 1989)
--Accelerating chylomicron and VLDL elimination from the blood
--Activation of peroxisome proliferator-activated receptor gamma (PPAR-gamma)--Omega-3s ramp up the cellular equipment used to convert fatty acids to energy (oxidation) (Gani 2008)

Combine omega-3 fatty acids from fish oil with wheat elimination and you have an extremely potent means of reducing triglycerides. Read a previous Heart Scan Blog post here to read how a patient reduced triglycerides 93.5% from 3100 mg/dl to 210 mg/dl in just a few weeks using fish oil and wheat elimination.

Fish oil makes you happy: Psychological distress and omega-3 index

For another perspective on omega-3 blood levels, here's an interesting study in northern Quebec Inuits.

Traditionally, Inuits consumed large quantities of omega-3-rich seal, fish, caribou, and whale, even eating the fat. However, like the rest of the world, modern Inuits have increased consumption of store-bought foods, largely processed carbohydrates. Along with this trend has emerged more heart disease, diabetes, and depression.

A group from Laval University and University of Guelph, both in Canada, examined the relationship of plasma EPA + DHA levels and measures of psychological distress. This group had previously shown that Inuits older than 50 years had twice the plasma omega-3 levels (11.5%) compared to those younger than 50 years (6.5%), reflecting the shift away from the traditional diet.

Psychological distress was measured with The Psychological Distress Index Santé-Québec Survey (PDISQS-14): the higher the score, the greater the psychological distress. (In the graphs, tertile 1 is least distressed; tertile 5 is most distressed. Sorry about the small chart graphic--click on the graphic to make it bigger.)


From Lucas M et al 2009 (http://www.nutrasource.ca/NDI/Assets/Articles/Plasma%20omega-3%20and%20psychological%20distress%20among%20Nunavik%20Inuit.pdf)

"Our main finding was that women in the second and third tertiles of EPA+DHA concentrations in plasma PLs [phospholipids] had a 3 times lower risk of having a high-level PD [psychological distress] score than women in the lowest tertile."

While the relationship is stronger for women, you can see that, the higher the EPA + DHA plasma level, the lower the likelihood of psychological distress. Interestingly, the tertile with the greatest distress and lowest EPA + DHA levels had a plasma level of 7.0-7.5%--far higher than average Americans.

(Plasma levels of EPA + DHA were used in this study, which tend to reflect more recent omega-3 intake than the more stable and slower-to-change RBC Omega-3 Index that we use. Plasma levels also tend to run about 10-20% lower than RBC levels.)

Of course, there's more to psychological distress than omega-3 blood levels. After all, eating fish or taking fish oil capsules won't make money worries go away or heal an unhappy marriage. But it is one variable that can be easily and safely remedied.

Hospitals are a hell of a place to get sick

I answered a page from a hospital nurse recently one evening while having dinner with the family.

RN: "This is Lonnie. I'm a nurse at _____ Hospital. I've got one of your patients here, Mrs. Carole Simpson. She's here for a knee replacement with Dr. Johnson. She says she's taking 12,000 units of vitamin D every day. That can't be right! So I'm calling to verify."

WD: "That's right. We gauge patients' vitamin D needs by blood levels of vitamin D. Carole has had perfect levels of vitamin D on that dose."

RN: "The pharmacist says he can replace it with a 50,000 unit tablet."

WD: "Well, go ahead while Carole's in the hospital. I'll just put her back on the real stuff when she leaves."

RN: "But the pharmacist says this is better and she won't have to take so many capsules. She takes six 2,000 unit capsules a day."

WD: "The 50,000 units you and the pharmacist are talking about is vitamin D2, or ergocalciferol, a non-human form. Carole is taking vitamin D3, or cholecalciferol, the human form. The last time I checked, Carole was human."

RN: (Long pause.) Can we just give her the 50,000 unit tablet?

WD: "Yes, you can. But you actually don't need to. In fact, it probably won't hurt anything to just hold the vitamin D altogether for the 3 days she's in the hospital, since the half-life of vitamin D is about 8 weeks. Her blood level will barely change by just holding it for 3 days, then resuming when she's discharged."

RN: (Another long pause.) Uh, okay. Can we just give her the 50,000 units?"

WD: "Yes, you can. No harm will be done. It's simply a less effective form. To be honest, once Carole leaves the hospital, I will just put her back on the vitamin D that she was taking."

RN: "Dr. Johnson was worried that it might make her bleed during surgery. Shouldn't we just stop it?"

WD: "No. Vitamin D has no effect on blood coagulation. So there's no concern about perioperative bleeding."

RN: "The pharmacist said the 50,000 unit tablet was better, also, because it's the prescription form, not an over-the-counter form."

WD: "I can only tell you that Carole has had perfect blood levels on the over-the-counter preparation she was taking. It works just fine."

RN: "Okay. I guess we''ll just give her the 50,000 unit tablet."


From the alarm it raises trying to administer nutritional supplements in a hospital, you'd think that Osama Bin Laden had been spotted on the premises.

I laugh about this every time it happens: A patient gets hospitalized for whatever reason and the hospital staff see the supplement list with vitamin D, fish oil at high doses, iodine, etc. and they panic. They tell the patient about bleeding, cancer, and death, issue stern warnings about how unreliable and dangerous nutritional supplements can be.

My view is the exact opposite: Nutritional supplements are a wonderful, incredibly varied, and effective array of substances that, when used properly, can provide all manner of benefits. While there are selected instances in which nutritional supplements do, indeed, have interactions with treatments provided in hospitals (e.g., Valerian root and general anesthesia), the vast majority of supplements have none.

Does fish oil cause blood thinning?

Omega-3 fatty acids from fish oil have the capacity to "thin the blood." In reality, omega-3s exert a mild platelet-blocking effect (platelet activation and "clumping" are part of clot formation), while also inhibiting arachidonic acid formation and thromboxane.

But can fish oil cause excessive bleeding?

This question comes up frequently in the office, particularly when my colleagues see the doses of fish oil we use for cardiovascular protection. "Why so much fish oil? That's too much blood thinning!"

The most recent addition to the conversation comes from a Philadelphia experience reported in the American Journal of Cardiology:

Comparison of bleeding complications with omega-3 fatty acids + aspirin + clopidogrel--versus--aspirin + clopidogrel in patients with cardiovascular disease.(Watson et al; Am J Cardiol 2009 Oct 15;104(8):1052-4).

All 364 subjects in the study took aspirin and Plavix (a platelet-inhibiting drug), mostly for coronary disease. Mean dose aspirin = 161 mg/day; mean dose Plavix = 75 mg/day. 182 of the subjects were also taking fish oil, mean dose 3000 mg with unspecified omega-3 content.

During nearly 3 years of observation, there was no excess of bleeding events in the group taking fish oil. (In fact, the group not taking fish oil had more bleeding events, though the difference fell short of achieving statistical significance.) Thus, 3000 mg per day of fish oil appeared to exert no observable increase in risk for bleeding. This is consistent with several other studies, including that including Coumadin (warfarin), with no increased bleeding risk when fish oil is added.

Rather than causing blood thinning, I prefer to think that omega-3 fatty acids from fish oil restore protection from abnormal clotting. Taking omega-3 fatty acids from fish oil simply restores a normal level of omega-3 fatty acids in the blood sufficient to strike a healthy balance between blood "thinning" and healthy blood clotting.

Heart Scan Blog readers take impressive doses of omega-3s

Here are the results from the latest Heart Scan Blog poll:

What is your dose of omega-3 fatty acids, EPA + DHA, from fish oil? (Add up the total content of EPA + DHA per capsules; multiply times number of capsules.)

The 479 respondents answered:

Less than 1000 mg per day
65 (13%)

1000-1999 mg per day
145 (30%)

2000-2999 mg per day
98 (20%)

3000-3999 mg per day
79 (16%)

4000-4999 mg per day
33 (6%)

5000-5999 mg per day
14 (2%)

6000 mg per day or more
45 (9%)


The poll did not discriminate between who has heart disease, who does not; who is taking omega-3 fatty acids for high triglycerides or for reduction of lipoprotein(a) (which requires high doses), or other indications. So variation is to be expected.

We can say that nearly all respondents are likely receiving sufficient omega-3s to impact cardiovascular risk, since the benefits begin just by consuming fish twice per month. I am especially impressed at the proportion of respondents (53%) who take at least 2000 mg per day of EPA + DHA. It's clear that people are really embracing the notion that omega-3 fatty acids pack a real wallop of health benefits.

Because different people in different situations and lipid/lipoprotein patterns have different omega-3 needs, there is really no "right" or "wrong" dose of omega-3 fatty acids.

However, there are several factors that enter into knowing your ideal omega-3 intake:

--Higher triglycerides require higher doses
--Lipoprotein(a) can respond to higher doses
--Having coronary or carotid plaque means you desire a "therapeutic" dose of omega-3s, not just a "preventive" dose

Time is a factor, also: The longer you take omega-3s, the higher your blood levels go. You can accelerate the replacement of non-omega-3s with higher doses of omega-3s.

But too much is not good either. Some participants in Track Your Plaque, for instance, have experimented with very high doses of EPA + DHA in the 9000-10,000 per day range and witnessed dramatic increases in LDL.

Much of the uncertainty about dosing will also be cleared up as we get more experience with the Omega-3 RBC Index, i.e, the proportion of fatty acids in red blood cells that are omega-3s. We are currently aiming for an Omega-3 Index of 10%, given the heart attack reductions observed at this level.