Harvard’s Advice Ends Low-Fat & Helps Stop Prediabetes

The prediabetes diet must include healthy natural fats if you want to reverse prediabetes and prevent full blown diabetes with all its potential complications that I know all too well.

I was pleased to see an article this week in my online edition of The Nutrition Source Update from the Harvard School of Public Health, April/May 2013 that stated:

It’s time to end the low-fat myth. That’s because the percentage of calories from fat that you eat, whether high or low, isn’t really linked with disease. What really matters is the type of fat you eat.

diabetes feet with ulcers on bottom

Diabetic foot wounds

Hooray, we are making progress on finally putting the low-fat mantra to rest!  I believe the low-fat public health policy that has been the mainstay of dietary advice in the U.S. has played some role in the burgeoning diabetes, prediabetes and obesity epidemics in our country.  These medical conditions cause countless complications of the feet and legs that I treat on a regular basis as a podiatrist and foot surgeon.

Harvard still has a way to go however.  In this same article, the author writes about so-called:

  • “good fats” defined as monounsaturated and polyunsaturated fats, and
  • “bad fats” defined as saturated fats and trans fats.

Trans fats should be avoided – although, believe it or not, there are some natural trans fats that actually have been shown to promote health. The trans fats that I am speaking about, the ones that cause health problems, are the product of the chemistry lab. They form as a result of “hydrogenating” vegetable oils to turn them from a liquid into a solid (margarine anyone?).  If you are reading about trans fats on a food label, they are not natural, they were man-made.

Regarding saturated fats – not all saturated fats are created equal.  I believe it is very likely that Harvard will eventually publish this information in a future article entitled, “Time to end the saturated fat myth” or “Not all saturated fats are harmful.”  In other words, our public health discussion on this topic will become more sophisticated, and we will not lump all saturated fats in with trans fats.

Just as the “low-fat” mantra was too simplistic, the ongoing drone of “saturated fats equals bad fats” is also going to lose its appeal under the light of future research. I believe this will become another mantra that will die a slow death, and it needs to go if we are to stop prediabetes, and end the diabesity epidemic in the United States and elsewhere. Saturated fat researchers are starting to suggest that we take a more sophisticated look at saturated fats in the diet.  The quote below illustrates this:

more recent investigations on the topic seem to have reconsidered the negative role of the dietary saturated fatty acids  as a risk factor for cardiovascular diseases and show that not only the type of fat, but also that the triglyceride structure plays a role in cholesterolaemia.  Source

coconutI predict the mainstream diet community will initially recognize saturated fats from plants such as coconut oil and palm oil as being eligible for the “good fats” moniker. They will then eventually recognize some animal-based saturated fats and Harvard will move them into the “good fat” category, in moderation. There is a glimpse of this in a paragraph taken from the article in The Nutrition Source Update April/May 2013 that I cited above. The author is hedging a bit, but in the future I imagine it will be said that a prediabetic and diabetic would be better off eating foods with “good saturated fats” in moderation as opposed to the starchy foods that raise blood sugar. Pay attention to the last line in bold so you can’t miss it.  🙂

“Low-fat,” “reduced fat,” or “fat-free” processed foods are not necessarily “healthy,” nor is it automatically healthier to follow a low-fat diet. One problem with a generic lower-fat diet is that it prompts most people to stop eating fats that are good for the heart along with those that are bad for it. And low-fat diets are often higher in refined carbohydrates and starches from foods like white rice, white bread, potatoes, and sugary drinks. Similarly, when food manufacturers take out fat, they often replace it with carbohydrates from sugar, refined grains, or starch. Our bodies digest these refined carbohydrates and starches very quickly, causing blood sugar and insulin levels to spike and then dip, which in turn leads to hunger, overeating, and weight gain. Over time, eating lots of “fast carbs” can raise the risk of heart disease and diabetes as much as—or more than—eating too much saturated fat.

Fast food hamburgers are not the best food, but is it really the burger that is the problem, or is it the bun? Is not the bun a “fast carb.”? We do not have a diabesity epidemic in our country because everyone’s pounding steak marinated in butter. I would suggest that it is not necessarily the fast food burger, it’s the bun, along with the French fries fried in vegetable oil.  Fats become a problem when eaten with the abundance of processed flour containing carbohydrate foods prevalent in our society today.  And that goes for all fats.  An abundance of “fast carbs” eaten along with fats is a combination that will disrupt your metabolism and set the stage for prediabetes.

Can our anestors give us some guidance for a good prediabetes diet?

Many of the regular Nutrientology readers know I typically take an ancestral approach  as a foundation to start thinking about food. This is simply how science works – it gains better insight into the present in the context of the past.  Astronomers look back in light years, geologists core the earth, and biologists look at fossils to better understand the nature of the present.  A similar approach can be used to better appreciate the relationship of food and physiology.  This approach does not negate, minimize or subjugate the present for the past.

Having said that, our developmental past is not consistent with how we currently eat. It does not mean that we cannot adapt to different foods, but the large amount of fats and carbohydrate foods we currently eat together in one sitting are gi-normous, some would even say super-sized. We simply do not have the metabolic machinery to process this type of food intake well.

There is some scant research to support the idea that fats become a health problem in the face of excessive carbohydrate intake.

These findings are consistent with the concept that dietary saturated fat is efficiently metabolized in the presence of low carbohydrate, and that a calorie restricted diet results in better preservation of plasma arachidonic acid.  Source

Humans evolved largely as hunter-gatherers. We hunted game and gathered plants. We ate more plants – they can’t run away. Many of you are familiar with the survivor television shows that have become popular in recent years. Think about what these survivors do. They look for edible plants, eat when they can, and try to figure out a way to trap some kind of animal.  Eat like a survivor.

We can now grow and mow down fields of grain to consume with our grain-fed fattened game. This does not mean that we cannot or should not eat some grains – although some nutritionists would go that far – it just means if you want to stop, and then reverse prediabetes metabolic syndrome, and prevent the potential full-blown complications that I see on a regular basis, you need to eat non-vegetable and non-fruit carbohydrate sources with discretion.

The Nutrition Source Update April/May 2013 cited above is also acting rather unsophisticated by lumping together all “vegetable oils” as “good fats.”

Foods high in good fats include vegetable oils (such as olive, canola, sunflower, soy, and corn)

This is not the best advice. While the nutrition literature supports substituting natural omega-6 containing foods, and not carbohydrates, for saturated fats, the omega-6 fats found in processed seed oils above are not necessarily “good fats.”    Things may not be so clear cut, particularly with regard to the vegetable oils labelled as “good fats” in the Harvard article cited above.  Recent research looked at the most abundant omega-6 fat called linoleic acid found in safflower oil and found that it may not be all that it’s cracked up to be.   This recent research – the result an updated meta-analysis of omega-6 linoleic acid trials – suggests that omega-6 oils may be a problem in that substituting omega-6 for saturated fat caused health problems:

Advice to substitute polyunsaturated fats for saturated fats is a key component of worldwide dietary guidelines for coronary heart disease risk reduction. However, clinical benefits of the most abundant polyunsaturated fatty acid, omega 6 linoleic acid, have not been established. In this cohort, substituting dietary linoleic acid in place of saturated fats increased the rates of death from all causes, coronary heart disease, and cardiovascular disease. An updated meta-analysis of linoleic acid intervention trials showed no evidence of cardiovascular benefit. These findings could have important implications for worldwide dietary advice to substitute omega 6 linoleic acid, or polyunsaturated fats in general, for saturated fats.  Source 

So why on the one hand does the use of omega-6 seem advisable, and on the other hand it may increase cardiovascular disease?

The studies in the meta-analysis cited above used safflower oil and safflower oil polyunsaturated margarine. These are processed vegetable oils.  They are not natural omega-6 fats, and this may be where the apparent conflicting health information regarding omega-6 resides. Natural omega-6 do not appear to have the negative health consequences of processed, or “adulterated” omega-6.  Researchers from the University of Florida found that:

unadulterated forms of LA are cardioprotective and should be consumed as part of a healthy diet. In contrast, abundant evidence now indicates that adulterated forms of LA, predominantly hydrogenated vegetable oils, are atherogenic and should not be considered part of a healthy diet. The ability to adulterate the natural omega-6 fatty acid, LA, has contributed to mixed findings regarding the effects of this fatty acid on cardiovascular health. Thus, it is critical that the source of LA be taken into account when drawing conclusions about the physiological effects of this fatty acid. The findings of the present review are in line with current dietary recommendations of the American Heart Association.

Free full text here.

This speaks to one of the basic principles of healthy eating – just eat real food – unprocessed plants and animals.  The best natural, a.k.a. “real food,” sources of chickensomega-6 fats for the prediabetes diet are chicken, nuts and seeds.

  • Think chicken and nuts/seeds for omega-6 containing animals and plants, respectively.
  • Think fish and flax for omega-3 containing animals and plants, respectively.

Another mantra that is being thrown over board in this landmark article out of Harvard is the “the avoid cholesterol containing foods at all costs” mantra. Getting rid of this simplistic nonsense will also help stop prediabetes.  It’s time to elevate our game regarding public health dietary education regarding fats and the natural healthy fat containing foods that should be eaten to help stop prediabetes, and put an end to the diabesity epidemic.

From The Nutrition Source Update from the Harvard School of Public Health, April/May 2013:

Although it is still important to limit the amount of cholesterol you eat, especially if you have diabetes, for most people dietary cholesterol isn’t nearly the villain it’s been portrayed to be….And the biggest influence on blood cholesterol level is the mix of fats and carbohydrates in your diet—not the amount of cholesterol you eat from food.

This is amazing to me. I wonder who this author is and how it got by the editorial board at Harvard? Winds of change may be coming to U.S. dietary public health policy…We can only hope so.

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About Robert Creighton

Dr. Creighton is a podiatrist and foot surgeon with over 26 years in podiatric practice treating thousands of patients afflicted with the physiological, physical, and psychological side effects and complications of diabetes and pre-diabetes metabolic syndrome. He believes these disorders present a pressing public health concern that need to be more actively addressed in a multidisciplinary way. Dr. Creighton graduated from what is now the Temple University School of Podiatric Medicine after receiving his undergraduate degree in Biology. He is certified by the American Board of Foot and Ankle Surgery, a member of the American Public Health Association, an American College of Sports Medicine certified personal trainer and a Member of the American Nutrition Association.

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One Response to Harvard’s Advice Ends Low-Fat & Helps Stop Prediabetes

  1. Michael Harris May 4, 2013 at 12:41 PM #

    Great, great post. I have shared it on Fitocracy, Facebook, and our Fitness and Nutrition Google+ community.

    A lot of my reading on the thinking behind government recommendations for dietary guidelines reveals a theme of “dumbing down” the science. When confronted with a complex theme, such as “good” fats versus “bad” fats, these bodies seem to operate from the assumption that the public can’t handle degrees of goodness. So, they paint with broad strokes, throwing the baby out with the bath water. These broad “definitive” guidelines seem to have the effect of taking the responsibility of understanding nutrition off the shoulders of the individual.

    The other infuriating part is how they constantly back in to existing conclusions (like cutting back on meats, for example) and try to walk some kind of insane tightrope between outdated, disproven (or never proven) science while incorporating the new knowledge. The result is the attitude, ever more pervasive, that “everything will kill you according to some study, so why should I care?”

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