How old are you?

George walks into my office. I ask him his age.

"I'm 21 years old," he declares.

Yet I look at George. He's got gray thinning hair, his posture is slumped forward rather than erect, the flesh on his upper arms hangs loosely, he's got wrinkles on his hands and face, brown spots on the back of his hands and arms. He looks more like 70 years old to me. "I don't think you're 21 years old. I think you're 70."

"Prove it," he says.

Okay. What now? Minus any formal identification like a driver's license, how do I prove that George is really 70-something and not 20-something? Not an easy thing, when you think about it. If George were a tree, I'd cut him down and count his rings. Is there such a phenomenon in humans?

This is actually a fascinating area of research, looking for reliable biomarkers of aging.

Among the most quantitative markers of aging is telomere length. Telomeres were once dismissed as nonsense sequences in DNA. However, more recent thought among geneticists is that telomeres shorten with aging and provide the body's cells a timeline of aging. This way, George's cells act like they are 70, not 13, and don't start producing gobs of growth hormone and testosterone in preparation for puberty.

What can slow or stall the shortening of telomere length? There are two I'm aware of:

1) Caloric deprivation--i.e., taking in fewer calories. This was among the theories explored by Dr. Roy Walford during his Biosphere2 experience, based on his work in mice that showed that caloric deprivation nearly doubled lifespan.

2) Vitamin D--Richards et al (2007) found that, the higher the vitamin D, the longer the telomere length. The highest vitamin D levels conferred a 5-year effective difference in telomere length.

So, if I could look inside George's cells and count his telomeres, I could judge with confidence whether he was 21 or 70. Or, he could take vitamin D sufficient to increase blood levels to a healthy range and be more like 65.

Comments (21) -

  • Ellen

    10/17/2009 11:20:26 AM |

    "gobs"


    Hahaha... I can so tell you are from Milwaukee. That is such a Wisconsin expression.  Laughing

  • LeonRover

    10/17/2009 9:44:35 PM |

    Another take on the Greek philosophical question: what is time? Even tho' they could count days and years, their answer was: "time is the measure of change". But perhaps that should be reversed to: "change is the measure of time".

    Doc, it seems to me the burden of proof was on the guy. You simply say: you only left high school three years ago? Gosh, there are no reports that any male has undergone the developmental changes I can see, in such a short time!
    Another point, the number of telomeres at the end of cells has to be calibrated against other measures, such as the sun going round the earth. All any particular individual has to claim is: my telomeres are lost 10 times faster than any one else's, now YOU prove otherwise.

    Y'all have a good day, now.

  • Anonymous

    10/17/2009 11:22:20 PM |

    "If George were a tree, I'd cut him down and count his rings"
    Too funny, Dr Davis.

    George's telomere's....reduced to T-stumps.

    Ellie

  • Telephone Triage

    10/18/2009 7:57:18 AM |

    Lovely blog...it is scary the way we are being attacked by the diseases at very early ages also.

  • Tim

    10/18/2009 9:26:05 AM |

    Al Sears says that high homocystein levels shortens telemores three times faster.

  • Peter

    10/18/2009 2:19:57 PM |

    I take vitamin D and I want to live longer.  I believe it will help because you said so,and I believe everything you say, including when you say you're not sure.

  • Peter

    10/18/2009 2:27:49 PM |

    Regarding "gobs", this is a popular expression in Oregon, too, and I'm not sure how you tell where an expression originated.

  • Dr. B G

    10/18/2009 6:41:26 PM |

    Very cool post, Dr. D!!!

    I've been into telomeres for awhile!!  Mag-deficiency is associated with reduced telomeres in vivo in rats(and reduced glutathione). HERE

    NAC can ameliorate some of the Mag-deficiency oxidative stress in vitro. NAC is the precursor for one of the most potent antioxidants, glutathione. HERE

    Glutathione peroxidases which generate more protective glutathione are selenium-containing enzymes. Selenium was correlated to longer telomeres and lower BP. Selenium.

    Glutathione strongly and positively affects telomere lengthening and telomerase activity. Role of nuclear glutathione as a key regulator of cell proliferation

    Curiously, (?via epigenetics and X-related telomere genetics?) maternal diet can shorten telomeres in rats. Epigenetics: maternal diet shortens aortic telomeres.

    Precursors of glutathione are:
    --NAC (sulfur proteins)
    --undenatured whey protein (sulfur proteins, like glutamine, arginine, taurine)
    --SAMe

    (PO suppl w/ GSH apparently doesn't work well)

    Of course there are many other ways to increase glutathione... Like the TYP program -- flavonoids, fish oil, alpha lipoic acid, MELATONIN, silymarin (WCCA's fave), selenium, magnesium, zinc, etc.

    I believe the omega-6:3 index is one of the best biomarkers for aging, at least until we can count our 'tree rings'! In post-MI rats, n-3 PUFAS increased glutathione and was incredibly protective. HERE

    The traditional 1960s rural Cretans shared the same low CAD rate as Japan with a high fat diet. To me,  the Cretan diet is  associated with high glutathione, selenium, low n-6, high high  n-3 ALA EPA DHA, 41% fat (like TYP Diet 3), intermittent fasting (Greek Orthodox practice), pastured-raised eggs, chicken, goat, mutton, wild seafood/snails, and very fatty sheep/goat yogurt and cheeses (rich in taurine and saturated fatty acids). HERE and HERE. And Simopoulus.

    -G

  • Dr. B G

    10/18/2009 6:41:26 PM |

    Very cool post, Dr. D!!!

    I've been into telomeres for awhile!!  Mag-deficiency is associated with reduced telomeres in vivo in rats(and reduced glutathione). HERE

    NAC can ameliorate some of the Mag-deficiency oxidative stress in vitro. NAC is the precursor for one of the most potent antioxidants, glutathione. HERE

    Glutathione peroxidases which generate more protective glutathione are selenium-containing enzymes. Selenium was correlated to longer telomeres and lower BP. Selenium.

    Glutathione strongly and positively affects telomere lengthening and telomerase activity. Role of nuclear glutathione as a key regulator of cell proliferation

    Curiously, (?via epigenetics and X-related telomere genetics?) maternal diet can shorten telomeres in rats. Epigenetics: maternal diet shortens aortic telomeres.

    Precursors of glutathione are:
    --NAC (sulfur proteins)
    --undenatured whey protein (sulfur proteins, like glutamine, arginine, taurine)
    --SAMe

    (PO suppl w/ GSH apparently doesn't work well)

    Of course there are many other ways to increase glutathione... Like the TYP program -- flavonoids, fish oil, alpha lipoic acid, MELATONIN, silymarin (WCCA's fave), selenium, magnesium, zinc, etc.

    I believe the omega-6:3 index is one of the best biomarkers for aging, at least until we can count our 'tree rings'! In post-MI rats, n-3 PUFAS increased glutathione and was incredibly protective. HERE

    The traditional 1960s rural Cretans shared the same low CAD rate as Japan with a high fat diet. To me,  the Cretan diet is  associated with high glutathione, selenium, low n-6, high high  n-3 ALA EPA DHA, 41% fat (like TYP Diet 3), intermittent fasting (Greek Orthodox practice), pastured-raised eggs, chicken, goat, mutton, wild seafood/snails, and very fatty sheep/goat yogurt and cheeses (rich in taurine and saturated fatty acids). HERE and HERE. And Simopoulus.

    -G

  • Matthew

    10/19/2009 12:54:33 AM |

    Dr. Davis,

    Have you heard about ELC (earlobe crease) as a possible key sign of aging? It seems that tons of studies show a very strong positive connection between younger people with an earlobe crease and CVD. What do you think?

  • David Throop

    10/19/2009 3:07:30 PM |

    Doc Davis,

    Last week, the U.S. Preventive Services Task Force came out with a review and with recommendations about using emerging risk factors for predicting and managing heart disease.  I think there's a lot in there that you'll agree with.  But they were negative about calcium scoring.

    Sandy Swarz, whose scholarship is pretty sharp, gives a summary.

    I'd really like to see your response to all this.

  • Michelle

    10/19/2009 7:54:03 PM |

    It is scary how many young people are getting elderly diseases. I know someone who died of a massive MI at the age of 26. I am also proof of that. I have CAD, hypothyriodism, Low Vitamin D, Low B12, gastritis, and valve disease and I am only 35. I am looking forward to being able to reverse some of these diseases naturally.

    Michelle

  • Dr. William Davis

    10/19/2009 9:58:42 PM |

    Hi, Matthew--

    I believe there's some evidence that ear lobe creases are associated with increased coronary risk, but I don't know of any data relating them in younger people specifically.

    I have one myself, and it's been there for as long as I can remember and does indeed correlate with my family's aggressive heart disease pattern.

  • Dr. William Davis

    10/19/2009 10:00:02 PM |

    Hi, G--

    As always, you are full of unique observations.


    Hi, Ellen--

    Perhaps I should have said "oodles."

  • rezzrovv

    10/20/2009 4:21:27 PM |

    Dr. Davis,

    See David Throop's comment above.  I actually came looking to see if you might have commented on this yet.  Curious your take.

    Scott Pierce

  • Anonymous

    10/22/2009 5:19:03 AM |

    Hi Dr. Davis,

    Have you observed a correlation between earlobe creases and coronary calcification among your patients?

    Thanks,

    David

  • Stan (Heretic)

    10/24/2009 5:06:47 PM |

    Hi Dr. B G,

    Interesting.  Magnesium deficiency vs telomeres length could also be explained as a secondary effect caused by the excessive metabolism of carbohydrates as the primary factor.  High magnesium intake is required for glucose metabolism, see for example Implications of oxidative stress in high sucrose low magnesium diet fed rats

    Similar situation may exist with glutathione, high glutatione may be a secondary marker for a diet high in dairy and (thus automatically) lower in carbohydrates.  This paper you linked Maternal diet influences DNA damage, aortic telomere length, oxidative stress, and antioxidant defense capacity in rats seems to be pointing to a high carb diet as one of the factors that may cause accelerated growth of low birth weight babies (the paper discusses human studies as well), which then is correlated with higher CVD risk, shorter telomeres and worsens other markers (bones abnormality etc).

       In contrast to this, high fat low carb nutrition seems to slow down babies and infants growth and slows the onset of puberty, which according to the logic presented by the papers discussed above, ought to reduce oxidative stress, slow down the shortnening of telomeres and reduce the CVD risk later in life.
    Regards,
    Stan

  • Dr. B G

    10/26/2009 4:44:49 PM |

    Hi Stan,

    Yes -- there are many implications to such data and other epi-genetic data. Low protein maternal  diets increase Met Syn for 2 generations in rat pups.

    Low Sat Fat maternal diets?  High carb, low protein, allergenic wheat maternal diets?  I believe we are epi-genetically affecting many future generations and their metabolism, growth hormone, thyroid hormone, leptin/ adiponectin and perhaps even vitamin D hormone pathways... This may explain why right now CAD and diabetes is rampant compared to just 1-2 generations ago. I have 80-90s year old patients how are 20x more healthier than my 30-40 year olds! Have we genetically predisposed ourselves to the 'over summer' mode that Dr. T at Nephropal has talked about by our mother's diets and her lack of sunlight, rich fatty foods, omega-3, and excess omega-6 in utero??

    I believe so.

    -G

  • Dr. B G

    10/26/2009 4:44:49 PM |

    Hi Stan,

    Yes -- there are many implications to such data and other epi-genetic data. Low protein maternal  diets increase Met Syn for 2 generations in rat pups.

    Low Sat Fat maternal diets?  High carb, low protein, allergenic wheat maternal diets?  I believe we are epi-genetically affecting many future generations and their metabolism, growth hormone, thyroid hormone, leptin/ adiponectin and perhaps even vitamin D hormone pathways... This may explain why right now CAD and diabetes is rampant compared to just 1-2 generations ago. I have 80-90s year old patients how are 20x more healthier than my 30-40 year olds! Have we genetically predisposed ourselves to the 'over summer' mode that Dr. T at Nephropal has talked about by our mother's diets and her lack of sunlight, rich fatty foods, omega-3, and excess omega-6 in utero??

    I believe so.

    -G

  • buy jeans

    11/3/2010 2:24:30 PM |

    However, more recent thought among geneticists is that telomeres shorten with aging and provide the body's cells a timeline of aging. This way, George's cells act like they are 70, not 13, and don't start producing gobs of growth hormone and testosterone in preparation for puberty.

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Family lessons

Lou was recovering from his 3rd bypass operation. This third go-round left him weaker, slower, less quick on the rebound. In fact, he was lucky to have survived.

At 71 years old, Lou went a good 15 years since his second bypass, another 10 years prior to his first bypass at age 46.

In the days immediately following Lou's bypass, I had a chance to talk to his son, who stayed at his Dad's bedside while Lou struggled through post-op recovery.

"Did your Dad tell you about why this has happened, what caused his heart disease?" I asked.

"Sort of. He just said I should get checked," Lou's son, Aaron, replied.

"Did he mention the lipoprotein(a) pattern he has?"

"No. He never mentioned anything like that. He just said to get checked."

That's how it gets played out more often than not: Mom or Dad has a heart attack, stents, or (3rd) bypass, the children are told to get checked. Getting "checked" assumes that the doctor knows what to check for.

In Lou's case, the reason why he was in the hospital getting his 3rd (and final) bypass was lipoprotein(a), along with genetically-determined small LDL particles, low HDL, a postprandial (after-eating) disorder, hypertension, and borderline diabetes, not to mention vitamin D deficiency, omega-3 fatty acid deficiency, and marginal thyroid function. (Lou, a retired city employee, had showed only marginal interest in correcting these patterns. While he accepted medications, he proved unwilling to engage in the diet and nutritional supplement strategies required to correct his patterns.)

So Lou's 3rd bypass operation provided a moment of reflection for Aaron to ask: "Could I share the fate of my Dad?" With Lou's combination of genetic patterns, there was at least a 75% likelihood that he did. Sadly, going to his doctor would likely yield little more than a cholesterol panel, a question about smoking, and a prescription for Lipitor.

Just getting "checked" would be, more than likely, a recipe for disaster for Aaron: heart disease in his 40s or 50s. That's why you need to take control over this sad state of affairs and ask--no, insist--that an effort be made to determine whether you might share your parents' fate.

Look like Jimmy Stewart


"This diet works great," Don declared. "But I think I've lost too much weight."

At 67 years old and 5 ft. 11 inches, Don began the program weighing 228 lbs (BMI 31.9). Because of high triglycerides, high blood sugar, high c-reactive protein, and excessive small LDL, I instructed Don to eliminate all wheat products from his diet, along with cornstarch and sweets. His intake of lean meats, eggs, vegetables, oils, raw nuts, etc. was unlimited.

Don now weighed 194 lbs, down 34 lbs over 6 months (BMI 27.1). Triglycerides, blood sugar, blood pressure, and well-being had improved dramatically; small LDL, however, had dropped only 30%--still room for improvement.

"My friends say I'm too skinny. They ask if I have cancer!"

I've heard this many times: Someone loses weight in a relatively short period of time and friends and family tell you you're too skinny. "It must be cancer. Nobody loses weight like that."

Unfortunately, many Americans have forgotten what normal looks like. Normal is certainly not a 190-lb, 5 ft 4 in woman, nor is it a 228 lb, 5 ft 11 inch man. But Americans have put on so much weight that the prevailing view of what constitutes "normal" weight has been revised upward. Normal is closer to what we see in old movies from the 1940s and '50s with people like Jimmy Stewart and Donna Reed. That's what we are supposed to look like.

So Don actually remains mildly overweight but is judged as "too skinny," or even cancer-ridden, by friends and family.

Ignore such comments. As you lose pounds and approach a truly desirable weight, realize that you are returning to the normal state, not the vision of "normal" now held by most Americans.

Getting vitamin D right

Vitamin D is, without a doubt, the most incredible "vitamin"/prohormone/neurosteroid I have ever encountered. Frankly, I don't know how we got anything accomplished in health pre-D.

Unfortunately, people I meet rarely take their vitamin D in a way that accomplishes full restoration of vitamin D blood levels. It really isn't that tough.

Here's a list of common tripping points with vitamin D:

"I take vitamin D: 1000 units a day."
This is probably the most common mistake I see: Taking a dose that is unlikely to yield a desirable blood level. (We use 60-70 ng/ml of 25-hydroxy vitamin D as our target.) Most men and women require 6000 units per day to achieve this level. There is substantial individual variation, however, with an occasional person needing much more, a rare person requiring as little as 1000 units.


"I bought some vitamin D on sale. They were white tablets."
Time and again, patients in my office who initially have had successful vitamin D replacement, despite being reminded that only oil-based forms should be taken, switch to tablets. While they initially showed a 25-hydroxy vitamin D blood level, for instance, of 67 ng/ml on 8000 units per day with an oil-based capsule, they switch to a tablet form and the next blood level is 25 ng/ml. In other words, tablets are very poorly or erratically absorbed.

I have had people use tablets successfully, however, by taking their vitamin D tablets with a teaspoon of oil, e.g., olive oil. Oil is necessary for full absorption.


"I'm going to Florida. I'll stop my vitamin D because I'm going to lay in the sun."
Wrong. 90% of adults over 40 years old have lost the majority of their ability to activate vitamin D in the skin. A typical response might be an increase in blood level from 25 to 35 ng/ml--a 10 ng increase with a dark brown tan.

There is an occasional person who, with sun exposure, increases blood levels substantially. This can occur in both fair-skinned and dark-skinned people, though I've never seen it happen in an African-American person. The occasional person who maintains the ability to convert vitamin D with sun exposure, or young people, should seasonally adjust their vitamin D dose, e.g., 6000 units winter, 3000 units summer, or some other regimen that maintains desirable blood levels. You can see that monitoring blood levels (we check levels every 6 months for the first 2 years) is crucial: You cannot know what your vitamin D needs are unless you assess 25-hydroxy vitamin D levels.


"I drink plenty of milk. I don't think I need to take vitamin D."
Oh, boy. This is so wrong on so many levels.

First of all, no adult should be drinking plenty of cow's milk. (A discussion for another day.) Second of all, cow's milk averages 70 units of vitamin D, often the D2 form (ergocalciferol), per 8 oz. Even if the FDA-mandated 100 units per day were present, an average adult dose of 6000 units would require 60 glasses of milk per day. Can you say "diarrhea"?

Likewise, other food sources of vitamin D, such as fish (300-400 units per serving) and egg yolks (20 units per yolk), are inadequate. This makes sense: Humans are not meant to obtain vitamin D from food, but from sun exposure over a large body surface area. And this is a phenomenon that is meant to occur only in the youthful, ensuring that nature takes its course and us older folks get old and make way for the young (i.e., unless we intervene by taking vitamin D supplements).


"My doctor said that my vitamin D blood level was fine. It was 32 ng/ml."

Let's face it: By necessity, your overworked primary care physician, who manages gout, hip arthritis, migraine headaches, stomach aches, prostate enlargement, H1N1, depression, etc., is an amateur at nearly everything, expert in nothing. Nobody can do it all and get it right. Likewise vitamin D. The uncertain primary care physician will simply follow the dictates of the laboratory form that specifies "30-100 ng/ml" as the "normal" or "reference range." Unfortunately, the laboratory often quotes population distributions of a lab measure, not an ideal or desirable level.

To illustrate the folly of population distributions of a measure, imagine you and I want to know what women weigh. We go to a local mall and weigh several thousand women. We tally up the results and find that women weigh 172 lbs +/- 25 lbs (the mean +/- 2 standard deviations). (That's true, by the way.) Is that desirable? Of course it isn't. Population average or population distribution does not necessarily mean ideal or desirable.


"My husband's doctor said he should take 4000 units per day. So I just take the same dose."
That would be fine if all adults required the same dose. However, individual needs can vary enormously. A dose that is grossly insufficient for one person may be excessive for another. Once again, vitamin D dose needs can be individualized by assessing 25-hydroxy vitamin levels in the blood.


"I don't need to take vitamin D. I already take fish oil."
I suspect this mistaken belief occurs either because people confuse fish oil with cod liver oil, which does contain some vitamin D. (Cod liver oil is not the best source of vitamin D, mostly because of the vitamin A content; also a discussion for another time), or because they've heard that eating fish provides vitamin D. However, fish oil capsules do not contain vitamin D unless it is added, in which case it should be prominently and explicitly stated on the label.


"I don't have to take vitamin D. It's summer."

For most people I know, if it's a bright, sunny July day, where are they likely to be? In an office, store, or home--NOT lying in the sun with a large body surface area exposed. Also, most people expose no more than 5-10% of surface area in public. I doubt you cut the grass in a bathing suit. Because of modern indoor lifestyles and fashion, the majority of adults need vitamin D supplementation year-round.


I advise everyone that gelcap vitamin D is preferable. Some, though not all, liquid drop forms have also worked. Take a dose that yields desirable blood levels. And blood levels of 25-hydroxy vitamin D are ideally checked every 6 months: in summer and in winter to provide feedback on how much sun activation of D you obtain.

If your doctor is unwilling or unable to perform vitamin D testing, fingerstick vitamin D test kits can be obtained from Track Your Plaque.

Jimmy Moore's thyroid adventure

My friend, Jimmy Moore of Living La Vida Low Carb, describes his thyroid experience here.

As Jimmy points out, he was looking for a way to jump-start a 50-lb weight loss. In my experience, low thyroid hormone levels ("hypothyroidism") are an exceptionally common cause for weight gain. Correcting even marginal hypothyroidism can facilitate weight loss, often resulting in 10 or more pounds of weight loss within the first month.

Unfortunately, Jimmy's thyroid hormone panel proved normal: TSH 1.3, thyroid hormones free T3 and free T4 in the mid- to upper-half of the reference range.

I say "unfortunately" because it is really an easy, inexpensive, and benign solution for losing weight. (I don't, of course, wish that Jimmy or anyone else develops a thyroid condition. But it really can provide gratifying weight loss results when thyroid function is low.) Jimmy might consider taking his oral temperature first thing in the morning as another means of assessing the adequacy of thyroid function.

Perhaps you will be luckier than Jimmy and have thyroid dysfunction that can be corrected and jump-start your weight loss program. Fingerstick thyroid test kits like the one Jimmy used are available here from Track Your Plaque.

What's that in your mouth?




Fat = triglycerides

In other words, eat fat, whether it's saturated, hydrogenated, polyunsaturated, or monounsaturated, and blood levels of triglycerides will go up over the next 6 hours. This remains true if there are carbohydrates in the meal, or if there are NO carbohydrates in the meal. It also remains true if you chronically consume fats.

While fats are the primary determinant of postprandial (after-eating) triglycerides, carbohydrates are the primary determinant of fasting triglycerides.

So, if your triglycerides are high on a fasting cholesterol (lipid) panel, it's most likely because you overconsume carbohydrates.


Thanks to cartoonist Eli Stein, who has generously allowed me to reprint his artwork on these pages. Mr. Stein has published his work in dozens of magazines and newspapers, including the Wall Street Journal, Barron's, and Good Housekeeping. More of his work can be found at Eli Stein Cartoons.

De Novo Lipo-what?

Humans have limited capacity to store carbohydrates. Beyond the glucose and glycogen in our blood and tissues, we have relatively little carbohydrate to draw from in time of energy need. That's why long-distance runners and triathletes have to carry sugar sources to keep blood sugar from plummeting.

Fat, of course, is different. We have virtually unlimited capacity to store energy as fat.

Because we have limited carbohydrate storage capacity, what can the body do with the excessive quantities of carbohydrates that Americans ingest? What becomes of a bagel for breakfast, wheat crackers for snacks, a whole wheat sandwich for lunch, pretzels, and whole wheat pasta that many people eat every day, not to mention the chips, soft drinks, and juices?

Excess carbohydrates are diverted to an interesting metabolic pathway called de novo lipogenesis (DNL). This refers to the liver's ability to make triglycerides from excessive carbohydrates in the diet. Triglycerides are packaged for release into the blood as VLDL. VLDL, in turn, interacts with other lipoproteins, creating small LDL particles, reduced HDL and smaller, less protective HDL. High VLDL will be measured on a standard cholesterol panel as higher triglycerides.

A University of California (Berkeley, San Francisco) group has done much of the work describing DNL.

A diet weighed towards carbohydrates, especially if 50% or greater calories are carbohydrate, is sufficient to provoke plenty of DNL, even in slender people. DNL is a big part of the reason why low-fat (and, thereby, high-carbohydrate) diets result in higher triglycerides. DNL really gets turned on many-fold if the carbohydrates are "simple," rather than "complex."

Overweight people, however, can demonstrate five-fold greater DNL even with lesser quantities of carbohydrate intake (e.g., 40% fat, 46% carbohydrate, 14% protein):





From Schwarz et al 2003. Mean (± SEM) fractional de novo lipogenesis in lean normoinsulinemic (NI), obese NI, and obese hyperinsulinemic (HI) subjects after 5 d of consuming a high-fat, low-carbohydrate diet and in different lean NI and obese HI subjects after 5 d of consuming a low-fat, high-carbohydrate diet. Values with different superscript letters are significantly different.


Excessive carbohydrates, a la standard low-fat diets, are good for nobody. The concept of de novo lipogenesis fills in a theoretical hole that now explains why people who eat carbohydrates have higher triglycerides, VLDL, and, eventually, insulin resistance and diabetes.

Gretchen's postprandial diet experiment II

I previously posted Gretchen's postprandial diet experiment, in which she consumed a low-fat diet for a day, followed by a low-carbohydrate diet for a day. Grethen monitored blood glucose and triglycerides with fingerstick checks. (Blood glucose can be checked on any widely available glucose monitor; triglycerides can be monitored with the Cardiochek device.)

Let's now discuss what happened.

On the low-carb, high-fat day, there was an initial surge in triglycerides to 250 mg/dl late morning, followed by a secondary peak several hours following dinner. Because fat is mostly triglycerides, Gretchen's high-fat (sausage, bacon, butter, whole-fat yogurt) breakfast provided a large quantity of triglycerides that needed to be absorbed. This generally occurs over approximately 6 hours, varying depending on body weight, how accustomed you are to fat, activity level during the day, the kind of fat in the meal. The high content of saturated fat in Gretchen's high-fat breakfast likely caused the somewhat slower drop in triglycerides over approximately 7 1/2 hours.

As Gretchen herself had noted, triglycerides the following day were lower, a typical low-carb response. Blood sugar throughout showed only minor variation, with only small postprandial increases.

Thus, Gretchen experienced what we'd expect with a low-carb, high-fat diet: an initial high surge in triglycerides, followed by a decline in fasting levels, while blood sugar shows a normal contour.







Now, the more confusing low-fat experience:



Blood glucose makes a striking peak at 200 mg/dl after the low-fat breakfast of pasta and rice, in contrast to the low-carb breakfast. Triglycerides behaved very differently from the low-carb experiment: While there was no initial postprandial surge, there was a late surge developing 6-24 hours later. The late surge continued into the next day, with fasting levels the following morning (210 mg/dl) exceeding the starting triglyceride level (60 mg/dl).

The one potentially confusing aspect of all this is Gretchen's late rise in triglycerides on the low-fat diet. This phenomenon is due to something called de novo lipogenesis, or the liver's conversion of carbohydrates to triglycerides that occurs when an excessive carbohydrate load comes through diet. Because the human body cannot store anything beyond a minor quantity of carbohydrates (as glucose and glycogen), carbohydrates are converted to fats.

Another factor causing the late triglyceride increase is insulin resistance, given the high blood sugar response. When insulin resistance is present, the activity of the enzyme, lipoprotein lipase, is reduced. Less lipoprotein lipase activity allows slower VLDL degradation, allowing VLDL (and thereby triglycerides contained in VLDL) to "stack up" in the blood. Thus, the higher triglycerides late after eating and into the next morning.

One issue to be aware of: Acute responses can differ from chronic responses. In other words, had Gretchen had the luxury (and time and money) to conduct the experiment over, say, 4 weeks, rather than a single day, there would be somewhat different responses. The best data on this come from Dr. Jeff Volek of the University of Connecticut, in which 4 weeks of low-carbohydrate eating modify fasting and postprandial responses over time.

Several conclusions can be made from Gretchen's experience:

1) Low-carb, high-fat acutely generates extravagant postprandial triglyceride responses.
2) Low-fat causes a late triglyceride surge and higher fasting triglycerides.
3) Low-fat leads to high blood sugars and, by implication, diabetes.


Both the low-carb and the low-fat responses are undesirable, both leading to increased risk for heart disease. Which is worse? I believe that low-fat is more destructive, since it leads over time to both high triglycerides and diabetes, while low-carb/high-fat only leads to postprandial triglyceride surges, at least acutely.

How to best balance the responses to reduce risk for heart disease? That's a discussion for future.


Again, my thanks to Gretchen and the substantial amount of effort that went into generating these numbers. More of Gretchens' own writing can be found on her blogs:
http://wildlyfluctuating.blogspot.com
http://www.healthcentral.com/diabetes/c/5068

A wheat-free 2010

A Heart Scan Blog reader sent this fascinating description of his wheat-free adventure.

Whenever I discuss this notion of going wheat-free and the incredible health effects that develop, I invariably receive comments or emails saying something like "I eat wheat and feel fine. That can't be true." The problem is that not everybody needs to go wheat-free. 20-30% of people can include wheat in their diet and suffer little more than weight gain, some not at all.

But stories like Michael's (below) are commonplace in my experience. I've had many patients who, at first, refused to believe that wheat exposure might be the underlying cause for health struggles. But they finally give it a try and find that rashes, arthritis, acid reflux, irritable bowel symptoms, mood swings, anger, etc. are miraculously improved or gone.

Anyway, hear what Michael has to tell us:


Dr. Davis,

I want to thank you. I was browsing the web a while back and happened to stumble upon your blog post about wheat belly. The first thing that caught my attention was that I thought you had somehow gotten a photograph of me. The young man you posted an image of looked exactly like me. So I read what you had to say. After reading, I thought "Four weeks isn’t so bad. I think I can handle this."

It has now been nine weeks and all I can say is that I am completely amazed. Let me say first that twice in the past twenty years I have been tested for allergies. The first time I was tested I showed a slight reaction to Timothy Grass, but not enough to cause me any problems. The second testing I did not show a reaction to anything. So, I have always assumed that my chronic sinus problem were due to sensitivities to environmental pollutions. Now I am not so sure. I would like to list for you everything that has happened to me since I eliminated wheat from my diet.

1. I have lost a total of 12 pounds in the last 9 weeks.
2. I have lost 1 ¼ inches of belly fat
3. I have lost a tremendous amount of fat from my neck.
4. My entire life I have had problems with oily hair. I could wash my hair and three hours later I looked as if I hadn’t washed in a week. Now my hair stays clean and soft for two to three days without shampoo.
5. My hair was always flat and stringy. Now it has lots of body.
6. I used to have thick layers of dry skin on my scalp. It would come loose in chunks as large as a fingernail. That dry scalp is gone.
7. I used to have dry flaky skin that seemed to secrete oil. That no longer happens. My skin is now soft and smooth.
8. I have lived with bad acne for at least 35 years. Now it is hard to find a pimple on my body.
9. I have always had to fight dehydration. That is no longer a problem.
10. I used to drink two large cups of coffee every morning just to be able to function. I now have enough energy that I have eliminated caffeine from my diet.
11. I sleep more soundly than ever before and my dreams are clear and vivid.
12. My thought processes are more active and clear than they have ever been.
13. My chronic sinus issue is now a thing of the past.
14. I used to have problems with getting the “shakes” if I had gone more than a couple of hours without eating. It was as if I was suffering from low blood sugar. I would even be afraid that I would pass out. Now all I feel is hunger. I can go all day without eating and never feel in danger of losing consciousness.


Today is Thursday. This past Monday my wife and I were eating out and I ordered a burger without a bun. What I didn’t realize was that the burger would arrive covered in onion rings. I knocked the mountain of onion rings onto the plate but there were still a couple that were embedded in the cheese. I decided, what the hell, a couple of onion rings shouldn’t make that much of a difference. I will not make that mistake again anytime soon. Within 30 minutes I felt like there was a steel spike going through my left eye socket. I don’t remember ever being in that much pain. My sinuses were exploding. This morning, as I write this, I still feel the vestiges of that pain. Just enough that I know it is there. But after two and a half days, I am at least able to function again.

I owe you a debt of gratitude. You may have just saved my life. In the very least you have given me the means to improve my life in ways that I never thought possible.

Thank you so much,
Michael B.



Now, if wheat exposure can do that in Michael, what damage can it do in other people?

Personally, I previously experienced many of the same symptoms that Michael suffered, all gone with wheat elimination.

My advice: If you have any inkling that you might have a wheat sensitivity, make a New Year's resolution to stay wheat-free for 4 weeks and see whether you can feel any difference. Not everybody will, but many will be telling us about the dramatic health turnarounds they experienced.

Lipoprotein lipase and you

Lipoprotein lipase can make the difference between having heart disease and not having it. Having sky-high triglycerides or normal triglycerides. It can mean dinner hanging around for over 12 hours in the bloodstream, rather than the usual 4-6 hours.

If you take niacin, you must exercise

We use a lot of niacin in the Track Your Plaque program.

Niacin:

--Increases HDL and shifts HDL towards the large, protective fraction

--Reduces small LDL--In fact, niacin is the best treatment we have to reduce small LDL after wheat elimination and carbohydrate reduction.

--Reduces fasting and postprandial (after-eating) triglycerides

--Reduces heart attack risk by 20-28%--even as a sole agent.


But . . . niacin also triggers higher blood sugar because it partially blocks the effects of insulin (insulin "resistance").

While the net effect of niacin remains positive, the provocation of insulin resistance is not such a good thing. Can it be minimized or eliminated?

Yes, through exercise. Here's one interesting observation in obese (BMI 34.0), sedentary men given placebo, exercise, niacin (1500 mg Niaspan, once per day), or niacin + exercise:





From Plaisance et al 2008.

Blood was drawn following a high-fat meal challenge. (Yes, a high-fat challenge, not a carbohydrate challenge. In this study, there were only 17 grams carbohydrates in the test meal, but 100 grams fat. More on this in future.) Exercise consisted of walking for 50 minutes at a moderate pace one hour prior to the meal challenge.

You can see from the graph that exercise partially corrected the increased insulin level provoked by niacin.

Judging from this and other studies, exercise can help minimize the insulin-blocking effects of niacin. It doesn't take much, just moderate exercise for at least 30 minutes.

Adequate sleep can also help, since sleep deprivation is a potent trigger for insulin resistance, only worsened in the presence of niacin. Vitamin D supplementation to achieve desirable blood levels (which I define as 60-70 ng/ml) is also an effective means to minimize this effect.