Vitamin K2, aspirin, fish oil and blood thinning

An interesting question came up from one of our Track Your Plaque Members on the Forum.

"I am now taking 9 mg of vitamin K1 and 1000 mcg of K2.

Does taking this supplement with this much K1 have a counteracting effect on the thinning/anticlotting properties of aspirin and fish oil that I also take?"


Great question (along with lots of other greater discussions we have on the Forum.)

The answer: Vitamin K should have no effect on the platelet-blocking effects of aspirin or fish oil. The majority of blood clot inhibiting effects of aspirin and fish oil arise from their ability to keep blood platelets from "clumping" (just like the TV commercials for Plavix).

Vitamin K, on the other hand, participates in the liver production of blood clotting factors (like II, VII, IX, and X, among others for you curious ones).

Thus, vitamin K-dependent clotting factors and platelet-blocking are two separate pathways to forming blood clots. Some of us refer to the difference as "red clots" from the vitamin K pathway and "white clots" from the platelet pathway, since they really do have this different physical appearance.

The vitamin K2 conversation, like that about vitamin D, is fascinating for its potential to provide the missing link between the tightly-tied fortunes of bone health and atherosclerosis. Why is someone with a high CT heart scan score far more likely to have osteoporosis? Vitamin D and K2 deficiency may provide the missing link for many people.

Comments (12) -

  • Anonymous

    5/28/2007 2:23:00 PM |

    Dear Dr. Davis;   thank you so much for your blog...praying you reach many people.

  • Anne

    5/28/2007 8:06:00 PM |

    Is there a test for K2 deficiency? I have both osteoporosis and CAD. I have asked my doctors about vitamin K, but neither could tell me anything about it.

    What is the difference between K1 and K2?

    Great blog. Thank you.

  • Dr. Davis

    5/29/2007 1:25:00 AM |

    Anne--
    I have not yet been able to find a laboratory that makes K2 measurements available. However, it is a safe assumption that, unless you ingest fermented traditional cheeses (not Velveeta, etc.), pate or liver, or natto (blechh!), then there's an excellent chance you are deficient. To my knowledge, there is also no definition of deficiency, even if we were able to obtain a blood value. This will unfold over the next two years as data trickles out and experience accumulates.

  • Cindy

    6/3/2007 1:40:00 AM |

    What is a good dose for Vitamin K? Sine I'm not much of a cheese eater, or liver for that matter, I figure it can't hurt to take a supplement....but have no idea how much to take!

  • Dr. Davis

    6/3/2007 2:51:00 AM |

    The problem is that there is no dose.
    Based on available data, we have been advocating a dose of 1000 mcg (1 mg) per day, though the evidence is, admittedly, slim to support this specific dose. Changes are possible--probable--in future, as the experience develops.

  • BelieveIt

    2/12/2008 2:30:00 AM |

    Vitamin K test available at http://search.lef.org/cgi-src-bin/MsmGo.exe?grab_id=0&page_id=4131&query=vitamin%20k%20testing&hiword=VITAM%20VITAMER%20VITAMERS%20VITAMI%20VITAMINA%20VITAMINC%20VITAMIND%20VITAMINE%20VITAMINES%20VITAMINIC%20VITAMINK%20VITAMINS%20k%20testing%20vitamin%20

    Differences between K1 & K2 also discussed at http://search.lef.org/cgi-src-bin/MsmGo.exe?grab_id=0&page_id=1152&query=VIT%20K1%20K2&hiword=K1%20K2%20VIT%20

    aCCORDING TO THE ABOVE:  Tufts University tests the vitamin content of foods for the U.S. Department of Agriculture which maintains a database. Not too long ago, new technology allowed a more precise determination of the vitamin K content of food. Using the new technology, Tufts researcher Dr. Sarah Booth discovered that the vitamin K content of most foods is lower than researchers previously thought.

    Green leafy vegetables supply 40-50% of vitamin K for most Americans. Vegetable oils are the next highest source. Hydrogenated oils (margarine, for example) create an unnatural form of K that may actually stop the vitamin from working.

    There are three different types of vitamin K: K1 which is from plants, K2 which is made by bacteria and K3 which is synthetic. Vitamin K3 is generally regarded as toxic because it generates free radicals. This version shows promise in the treatment of cancer. K2 specifically keeps calcium and phosphorus out of the aorta, and reverses the effects of heart-unfriendly diets. The body converts K1 to K2.

    Dosage and precautions

    Vitamin K is not stored in the body, and is therefore nontoxic in high amounts. Forty-five milligrams a day were used in osteoporosis studies without any ill effect. Vitamin K has been approved in Japan for the treatment of osteoporosis since 1995. Several thousand times more than what people are currently getting in their diet has been taken without any toxicity. Dosage depends on an individual's diet, age, whether they are taking drugs, and what stressors are present. Generally, 10 mg/day is recommended.

    If you want to get your vitamin K level tested, request the osteocalcin test. It is much more reliable than coagulation tests. The osteocalcin test measures how much carboxylated osteocalcin you have. Since carboxylation is dependent on vitamin K, this test will give you a good idea of your vitamin K status, and whether or not you're headed for osteoporosis and possibly heart disease.

  • Anonymous

    1/16/2009 11:29:00 PM |

    An article at the Weston Price Foundation suggests that high amounts of vitamin K1 supplementation might not be correct. The author states:

    These results show that our absorption of the vitamin [k1] declines as the amount we consume increases and strengthens the interpretation that we might only be able to absorb about 200 micrograms per day. [of K1 from vegtables] …

    Preliminary evidence indicates that doses of 1000 micrograms per day of supplemental K1 may contribute to periodontal disease,31 suggesting that our bodies' resistance to absorbing this much K1 from vegetables may serve an important purpose.

    www.westonaprice.org/basicnutrition/vitamin-k2.html

  • Anonymous

    4/16/2009 2:49:00 PM |

    My mother-in-law is taking nattokinase for blood clot protection and disolving a clot in her caratoid retinal artery. Would taking K2 with natto kinase interfere with the clot disolving action of nattokinase?

  • Anonymous

    4/16/2009 2:51:00 PM |

    My motherinlaw is taking nattokinase and k2 together. She had a clot in her retinal artery causing some vision loss. Would taking k2 together with nattokinase dimish of help the nattokinase effect of disolving this blood clot?

  • Sal

    7/29/2009 4:52:05 AM |

    Dear Mr Davis

    Iam  lately diagnosed with arterial calcification in my lower limbs. I have no diabetes, no cholestrol issues nor any kidney or blood pressure issues, yeah I do have some anxiety.

    Please tell me whether taking vitamin k2 supplements would help. Also is there a test to find out if I am defecient in vitamink. What is the best supplement I can take.
    Thanks

    Kindest Regards
    Salim Khatri

  • Anonymous

    11/19/2009 2:30:39 AM |

    Actually, aspirin is a vitamin K antagonist. It is sort of silly to take an antagonist AND vitamin K.
    Further, if aspirin effectively blocks the K from working, the aspirin is maybe preventing platelets from clumping, but preventing inappropriate calcium deposition and therefore leading (over a long time) to arteriosclerosis and therefore CVD.
    Vitamin K2 is made by bacteria and found in fermented foods and animal organ meats. These are two food groups that have strong cultural ties, but they are lost as various cultures have blended into the American culture of some pretty heinous foods.
    So eat sausage, sauerkraut, pickles, natto, kimchee, organ meats and avoid pasteurized of the above and this may kill the bacteria that are making the K2.

  • buy jeans

    11/3/2010 10:32:34 PM |

    Vitamin K, on the other hand, participates in the liver production of blood clotting factors (like II, VII, IX, and X, among others for you curious ones).

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Overweight, hungry, diabetic, and fat-free

Let me tell you about my low-fat experience from 20 years ago.

At the time, I was living in Cleveland, Ohio, and served on the faculty at a large metropolitan university-affiliated hospital, supervising fellows-in-training and developing high-tech cath lab procedures like directional athererectomy and excimer laser coronary angioplasty. (Yes, another life.)

I was concerned about personal heart disease risk, though I knew next to nothing about lipids and coronary risk prediction outside of the little I learned in training and what the drug industry promoted.

I heard Dr. Dean Ornish talk while attending the American College of Cardiology meetings in Atlanta. Dr. Ornish spoke persuasively about the dangers of fat in the diet and how he "reversed" coronary disease using a low-fat, no added oils, no meat, vegetarian diet that included plenty of whole grains. So I thought I'd give it a try.

I eliminated all oils; I removed all meat, eggs, and fish from my diet. I shunned all nuts. I ate only low-fat products like low-fat yogurt and cottage cheese; and focused on vegetables, fruit, and whole grains. Beans and brown or wild rice were a frequent staple. I loved oatmeal cookies--low-fat, of course!

After one year of this low-fat program, I had gained a total of 31 lbs, going from 155 lbs to 186 lbs. I reassessed some basic labs:

HDL 28 mg/dl
Triglycerides 336 mg/dl
Blood sugar 151 mg/dl (fasting)


I became a diabetic. All through this time, I was also jogging. I ran on the beautiful paths along the Chagrin River in suburban Cleveland for miles north and south. I ran 5 miles per day most days of the week.

It was diabetes that hit me alongside the head: I was eating low-fat meticulously, exercising more than 90% of the population, yet I got fat and diabetic!

I have since changed course in diet. Last time I checked, my lipid values on NO statin agent:

HDL 67 mg/dl
Triglycerides 57 mg/dl
Blood sugar 91 mg/dl

That was my lesson that fat restriction is a destructive, misguided notion. The data since then have confirmed that restricting total fat is unnecessary, even undesirable, when fat calories are replaced by carbohydrate calories.

This is your brain on wheat

Here's just a smattering of the studies performed over the past 30 years on the psychological effects of wheat consumption.

Oddly, this never makes the popular press. But wheat underlies schizophrenia, bipolar illness, behavioral outbursts in autism, Huntington's disease, and attention deficit hyperactivity disorder (ADHD).

The relationship is especially compelling with schizophrenia:

Opioid peptides derived from food proteins: The exorphins.
Zioudrou C et al 1979
"Wheat gluten has been implicated by Dohan and his colleagues in the etiology of schizophrenia and supporting evidence has been provided by others. Our experiments provide a plausible biochemical mechanism for such a role, in the demonstration of the conversion of gluten into peptides with potential central nerovus system actions."


Wheat gluten as a pathogenic factor in schizophrenia
Singh MM et al 1976
"Schizophrenics maintained on a cereal grain-free and milk-free diet and receiving optimal treatment with neuropleptics showed an interruption or reversal of their therapeutic progress during a period of "blind" wheat gluten challenge. The exacerbation of the disease process was not due to variations in neuroleptic doses. After termination of the gluten challenge, the course of improvement was reinstated. The observed effects seemed to be due to a primary schizophrenia-promoting effect of wheat gluten."


Demonstration of high opioid-like activity in isolated peptides from wheat gluten hydrolysates
Huebner FR et al 1984


Is schizophrenia rare if grain is rare?
Dohan FC et al 1984
"Epidemiologic studies demonstrated a strong, dose-dependent relationship between grain intake and the occurrence of schizophrenia."

Small LDL: Perfect index of carbohydrate intake

Measuring the number of small LDL particles is the best index of carbohydrate intake I know of, better than even blood sugar and triglycerides.

In other words, increase carbohydrate intake and small LDL particles increase. Decrease carbohydrates and small LDL particles decrease.

Why?

Carbohydrates increase small LDL via a multistep process:

First step: Increased fatty acid and apoprotein B production in the liver, which leads to increased VLDL production. (Apoprotein B is the principal protein of VLDL and LDL)

Second step: Greater VLDL availability causes triglyceride-rich VLDL to interact with other particles, namely LDL and HDL, enriching them in triglycerides (via the action of cholesteryl-ester transfer protein, or CETP). Much VLDL is converted to LDL.

Third step: Triglyceride-rich LDL is "remodeled" by enzymes like hepatic lipase, which create small LDL.


Carbohydrates, especially if they contain fructose, also prolong the period of time that triglyceride-rich VLDL particles persist in the blood, allowing more time for VLDL to interact with LDL.

Many people are confused by this. "You mean to tell me that reducing carbohydrates reduces LDL cholesterol?" Yes, absolutely. While the world talks about cutting saturated fats and taking statin drugs, cutting carbohydrates, especially wheat (the most offensive of all), cornstarch, and sugars, is the real key to dropping LDL.

However, the effect will not be fully evident if you just look at the crude conventional calculated (Friedewald) LDL cholesterol. This is because restricting carbohydrates not only reduces small LDL, it also increases LDL particle size. This make the calculated Friedewald go up, or it blunts its decrease. Conventional calculated LDL will therefore either underestimate or even conceal the real LDL-reducing effect.

The reduction in LDL is readily apparent if you look at the superior measures, LDL particle number (by NMR) or apoprotein B. Dramatic reductions will be apparent with a reduction in carbohydrates.

Small LDL therefore serves as a sensitive index of carbohydrate intake, one that responds literally within hours of a change in food choices. Anyone following the crude Friedewald calculated LDL will likely not see this. This includes the thousands of clinical studies that rely on this unreliable measure and come to the conclusion that a low-fat diet reduces LDL cholesterol.

Fat "conditioning"

Here's a great study from the prolific laboratory of Dr. Jeff Volek from the University of Connecticut. (Full text here.)


http://jn.nutrition.org/cgi/content/full/134/4/880

Video Teleconference with Dr. William Davis


Dr. Davis is available for personal
one-on-one video teleconferencing

to discuss your heart health issues.


You can obtain Dr. Davis' expertise on issues important to your health, including:

Lipoprotein assessment

Heart scans and coronary calcium scores

Diet and nutrition

Weight loss

Vitamin D supplementation for optimal health

Proper use of omega-3 fatty acids/fish oil



Each personalized session is 30 minutes long and by appointment only. To arrange for a Video Teleconference, go to our Contact Page and specify Video Teleconference in your e-mail. We will contact you as soon as possible on how to arrange the teleconference.


The cost for each 30-minute session is $375, payable in advance. 30-minute follow-up sessions are $275.

(Track Your Plaque Members: Our Member cost is $300 for a 30-minute session; 30-minute follow-up sessions are $200.)

After the completion of your Video Teleconference session, a summary of the important issues discussed will be sent to you.

The Video Teleconference is not meant to replace the opinion of your doctor, nor diagnose or treat any condition. It is simply meant to provide additional discussion about your health issues that should be discussed further with your healthcare provider. Prescriptions cannot be provided.

Note: For an optimal experience, you will need a computer equipped with a microphone and video camera. (Video camera is optional; you will be able to see Dr. Davis, but he will not be able to see you if you lack a camera.)

We use Skype for video teleconferencing. If you do not have Skype or are unfamiliar with this service, our staff will walk you through the few steps required.

Track Your Plaque challenges

Of all the various factors we correct in the Track Your Plaque program in the name of achieving reversal of coronary plaque, there are two factors that are proving to be our greatest challenges:

1) Genetic small LDL

2) Lipoprotein(a)

More and more people are enjoying at least marked slowing, if not zero change or reduction, in heart scan scores following the Track Your Plaque program. We achieve this by correcting a number of factors. Some factors, like vitamin D deficiency, are easily corrected to perfection--supplement sufficient vitamin D to achieve a blood level of 25-hydroxy vitamin D of 60-70 ng/ml. Correcting standard lipid values--LDL cholesterol, HDL cholesterol, and triglycerides--child's play, even to our strict targets of 60-60-60.

However, what I call "genetic small LDL" and a subset of lipoprotein(a) are proving to be the most resistant of all.

Let's first consider genetic small LDL. Small LDL is generally the pattern of the carbohydrate-ingesting, overweight person. It has exploded in severity over the past decade due to overconsumption of carbohydrates due to the ridiculous low-fat notion. Reduce or eliminate carbohydrates, especially wheat, which permits weight loss, and small LDL drops like a stone. But there is a unique subset of people who express the small LDL pattern who start at or near ideal weight. Take Chad, for instance. At 6' 2" and 152 lbs and BMI of 19.6, there's no way excess weight could be triggering his small LDL. Yet he starts with 100% small LDL particles. All efforts to reduce small LDL, such as wheat, cornstarch, and sugar elimination; niacin; vitamin D normalization; thyroid normalization; and several supplements that yield variable effects, such as phosphatidylcholine, all leave Chad with more than 90% small LDL.

Lipoprotein(a) is a bit different. Over the past 5 years, our choices in ways to reduce Lp(a) expression have improved dramatically. Beyond niacin, we now have high-dose EPA + DHA, thyroid normalization that includes use of T3, and hormonal manipulation. In the Track Your Plaque experience, approximately 70% of people with Lp(a) respond with a reduction in Lp(a). (In fact, the 4 out of the 5 record holders for reduction of heart scan scores have Lp(a) that was successfully treated.) But about 30% of people with Lp(a) prove resistant to all these treatments--they begin with a Lp(a) of, say, 260 nmol/L and, despite niacin, high-dose EPA + DHA, and various hormones, stay at 260 nmol/L. It can be frustrating and frightening.

So these are the two true problem areas for the Track Your Plaque program, genetic small LDL and a subset of Lp(a).

We are actively searching for better options for these two problem areas. Given the collective exploration and wisdom that develops from such collaborative efforts as the Track Your Plaque Forum, I am optimistic that we will have better answers for these two stumbling blocks to plaque reversal in the future.

I'll supply the tar if you supply the feathers

The results of the latest Heart Scan Blog poll are in.


DIRECT-TO-CONSUMER PHARMACEUTICAL ADVERTISING HAS:

Increased public awareness of medical conditions and their treatment
19 (11%)

Has had little overall effect on health and healthcare
29 (18%)

Needlessly increased healthcare costs
81 (50%)

Further empowered the revenue-obsessed pharmaceutical industry
130 (81%)


Clearly, there's a lot of negative sentiment against direct-to-consumer (DTC) drug advertising.

It looks as if a small minority believe that good has come from DTC advertising, judging by the meager 11% who voted for increased awareness. In fact, the poll results are heavily weighed towards the negative: 50% voted for "needlessly increased healthcare costs," while an astounding 81% voted for "empowered the revenue-obsessed pharmaceutical industry."

It is, indeed, an odd situation: Pharmaceutical agents available only by prescription being hyped directly to the consumer.

Personally, I would vote for choices 1,3, and 4. While awareness has increased, it has come with a hefty price, not all of it well spent. I believe the pharmaceutical industry still adheres to the rule that, for every $1 spent on advertising, $4 is made in revenue. They are, in effect, printing money.

What goes up can't come down

According to conventional wisdom, heart scan scores cannot be reduced.

In other words, say you begin with a heart scan score of 300. Conventional wisdom says you should take aspirin and a statin drug, eat a low-fat "heart healthy" diet, and take high blood pressure medications, if necessary.

If your heart scan score goes up in a year or two, especially at an annual rate of 20% or more, then you are at very high risk for heart attack. If the heart scan score stays the same, then your risk is much reduced. These observations are well-established.

But more than 99% of physicians will tell you that reducing your heart scan score is impossible. Don't even try: Heart scan scores can go up, but they can't go down.

Baloney. Heart scan scores can indeed go down. And they can go down dramatically.

It is true that, following conventional advice like taking a statin drug, following a low-fat diet, and taking aspirin will fail to reduce your heart scan score. A more rational approach that 1) identifies all causes of coronary plaque, 2) corrects all causes while including crucial strategies like omega-3 fatty acid supplementation, vitamin D supplementation, and thyroid function normalization, is far more likely to yield a halt or reduction in score.

While not everybody who undertakes the Track Your Plaque program will succeed in reducing their heart scan score, a growing number are enjoying success.

A small portion of our experience was documented this past summer. (I collected and analyzed the data with the help of Rush University nutrition scientist, Dr. Susie Rockway, and statistician, Dr. Mary Kwasny.)


Effect of a combined therapeutic approach of intensive lipid management, omega-3 fatty acid supplementation, and increased serum 25 (OH) vitamin D on coronary calcium scores in asymptomatic adults.

Davis W, Rockway S, Kwasny M.

The impact of intensive lipid management, omega-3 fatty acid, and vitamin D3 supplementation on atherosclerotic plaque was assessed through serial computed tomography coronary calcium scoring (CCS). Low-density lipoprotein cholesterol reduction with statin therapy has not been shown to reduce or slow progression of serial CCS in several recent studies, casting doubt on the usefulness of this approach for tracking atherosclerotic progression. In an open-label study, 45 male and female subjects with CCS of > or = 50 without symptoms of heart disease were treated with statin therapy, niacin, and omega-3 fatty acid supplementation to achieve low-density lipoprotein cholesterol and triglycerides < or = 60 mg/dL; high-density lipoprotein > or = 60 mg/dL; and vitamin D3 supplementation to achieve serum levels of > or = 50 ng/mL 25(OH) vitamin D, in addition to diet advice. Lipid profiles of subjects were significantly changed as follows: total cholesterol -24%, low-density lipoprotein -41%; triglycerides -42%, high-density lipoprotein +19%, and mean serum 25(OH) vitamin D levels +83%. After a mean of 18 months, 20 subjects experienced decrease in CCS with mean change of -14.5% (range 0% to -64%); 22 subjects experienced no change or slow annual rate of CCS increase of +12% (range 1%-29%). Only 3 subjects experienced annual CCS progression exceeding 29% (44%-71%). Despite wide variation in response, substantial reduction of CCS was achieved in 44% of subjects and slowed plaque growth in 49% of the subjects applying a broad treatment program.

Gretchen's postprandial diet experiment

Gretchen sent me the results of a little experiment she ran on herself. She measured blood glucose and triglycerides after 1) a low-fat diet and 2) a low-carb diet.









Gretchen describes her experience:

Several years ago I received a windfall of triglyceride strips that would expire in a week or so. I hated to waste them, so I decided to use them to test my triglyceride and BG responses to two different diets: low carb and low fat.

The first day I followed a low-fat diet. For breakfast I ate a lot of carbohydrate, including 1 oz of spaghetti cooked al dente and ¾ cup of white rice. For the rest of the day I ate less carbohydrate but continued to eat low fat.

The second day I followed a low-carb diet. For breakfast I ate a lot of fat, including a sausage, mushrooms fried in butter, 2 slices of bacon, and ¼ cup of the creamy topping of whole-milk yogurt. For the rest of the day I ate less fat, especially less saturated fat, but continued to eat low carb.

Both days I measured both BG and triglyceride levels every hour until I went to bed. On the low-carb day I had 3 meals. On the low-fat day, I was constantly hungry, had 4 meals, and kept snacking.

You can see the results in Figure 1. On the low-fat diet, after a “healthy” low-fat breakfast of low-glycemic pasta with low-fat sauce, my BG levels shot up to over 200 mg/dL and took more than 6 hours to come down. My triglycerides, however, remained low, and at first I thought perhaps the low-fat diet might be better overall. However, after about 6 hours, the triglyceride levels started to increase steadily, and by the next morning, they were higher than they had been the day before.
On the low-carb diet, my BG levels stayed low all day. However, after meals, the triglyceride levels skyrocketed. After meals they came down, and by the next morning they were lower than they had been the day before.

As I interpret these results, the high triglyceride levels after eating the high-fat meals represent chylomicrons, the lipoproteins that transport fat from your meals to the cells of your body. The high triglyceride levels the morning after eating the low-fat meals represent very low density lipoprotein, which takes the cholesterol your liver synthesizes when your intake of dietary cholesterol is low and distributes it to cells that need it, or again, to the fat for storage.

There are several interesting factors to consider here. First, when you have a lipid test done at the lab, it’s usually done fasting, which means first thing in the morning after not eating for 8 to 12 hours. It tells you nothing about what your triglyceride levels were all day.

Second, the low-carb diet resulted in lower fasting triglyceride levels, but much higher postprandial triglyceride levels. Which are more dangerous? I’m afraid I don’t know. You should also note that the high-fat, low-carb breakfast was extremely high in fat, including saturated fat. I don’t normally eat that much fat but wanted to test extremes.

Third, although the low-fat diet didn’t produce the very high postprandial triglyceride levels that the high-fat diet did, it produced extremely high BG levels that persisted for 6 hours. Some people think that it’s oxidized and glycated lipids that are the dangerous ones, so high BG levels and normal triglyceride levels might be more dangerous than very high triglyceride levels and normal BG levels. Note that high BG levels also contribute to oxidation rates.

Fourth, this shows the results of an experiment with a sample size of one. My physiology might not be typical. If you want to know how your own body’s lipids respond to different types of diets, you should get a lipid meter and test yourself. Unfortunately, your insurance is unlikely to want to pay for this, so it will be an expensive experiment.

The main point of this is that the results of different diets are complex. We have to eat. And what we eat can affect many different systems in our bodies. Finding the ideal diet that matches our own physiology and results in the best lipid levels as well as BG levels is a real challenge.



This was a lot of effort for one person. Thanks to Gretchen for sharing her interesting experience.

Gretchen makes a crucial point: Some of the effects of diet changes evolve over time, much as triglyceride levels changed substantially for her on the day following her experiment. Wouldn't it be interesting to see how postprandial patterns develop over time if levels were observed sequentially, day after day?

The stark contrast in blood sugars is impressive--Low-carb clearly has the advantage here. Are there manipulations in diet composition in low-carb meals that we can make to blunt the early (3-6 hour) postprandial lipoprotein (triglyceride) peak? That's a topic we will consider in future.

More of Gretchen's thoughts can be found at:

http://wildlyfluctuating.blogspot.com
http://www.healthcentral.com/diabetes/c/5068

After-eating effects: Carbohydrates vs. fats

In the ongoing debate over whether it's fat or carbohydrate restriction that leads to weight loss and health, here's another study from the Oxford group examining the postprandial (after-eating) effects of a low-fat vs. low-carbohydrate diet. (Roberts R et al, 2008; full-text here.)

High-carbohydrate was defined as 15% protein; 10% fat; 75% carbohydrate (by calories), with starch:sugar 70:30.

High-fat was defined as 15% protein; 40% fat; 45% carbohydrate, with starch:sugar 70:30. (Yes, I know. By our standards, the "high-fat" diet was moderate-fat, moderate-carbohydrate--too high in carbohydrates.)

Blood was drawn over 6 hours following the test meal.




Roberts R et al. Am J Clin Nutr 2008

The upper left graph is the one of interest. Note that, after the high-carbohydrate diet (solid circles), triglyceride levels are twice that occurring after the high-fat diet (open circles). Triglycerides are a surrogate for chylomicron and VLDL postprandial lipoproteins; thus, after the high-carbohydrate diet, postprandial particles are present at much higher levels than after the high-fat diet. (It would have been interesting to have seen a true low-carbohydrate diet for comparison.) Also note that, not only are triglyceride levels higher after high-carbohydrate intake, but they remain sustained at the 6-hour mark, unlike the sharper decline after high-fat.

It's counterintuitive: Postprandial lipoproteins, you'd think, would be plentiful after ingesting a large quantity of fat, since fat must be absorbed via chylomicrons into the bloodstream. But it's carbohydrates (and obesity, a huge effect; more on that in future) that figure most prominently in determining the pattern and magnitude of postprandial triglycerides and lipoproteins. Much of this effect develops by way of de novo lipogenesis, the generation of new lipoproteins like VLDL after carbohydrate ingestion.

We also see this in our Track Your Plaque experience. Rather than formal postprandial meal-testing, we use intermediate-density lipoprotein (IDL) as our surrogate for postprandial measures. A low-carbohydrate diet reduces IDL dramatically, as do omega-3 fatty acids from fish oil.