Category Archives: Vitamins

My Critique of the Joslin Critique of the Paleo Diet

paleo diet, Paleolithic diet, hunter-gatherer diet

Huaorani hunter in Ecuador

The Joslin Diabetes Blog yesterday reviewed the paleo diet as applied to both diabetes and the general public.  They weren’t very favorably impressed with it.  But in view of Joslin’s great reputation, we need to give serious consideration to their ideas.  (I don’t know who wrote the review other than “Joslin Communications.”)

These are the main criticisms:

  • diets omitting grains and dairy are deficient in calcium and possibly B vitamins
  • you could eat too much total and saturated fat, leading to insulin resistance (whether type 1 or 2 diabetes) and heart disease
  • it’s not very practical, partly because it goes against the grain of modern Western cultures
  • it may be expensive (citing the cost of meat, and I’d mention fresh fruit and vegetables, too)

Their conclusion:

There are certainly better diets out there, but if you are going to follow this one, do yourself a favor, take a calcium supplement and meet with a registered dietitian who is also a certified diabetes educator  to make sure it is nutritionally complete, isn’t raising your lipids and doesn’t cause you any low blood glucose incidences.

Expense and Practicality

These take a back seat to the health issues in my view.  Diabetes itself is expensive and impractical.  Expense and practicality are highly variable, idiosyncratic matters to be pondered and decided by the individual.  If there are real health benefits to the paleo diet, many folks will find work-arounds for any expense and impracticality.  If the paleo diet  allows use of fewer drugs and helps avoid medical complications, you save money in health care costs that you can put into food.  Not to mention quality of life issues (but I just did).

Calcium and B Vitamin Deficiencies

This is the first I’ve heard of possible B vitamin deficiencies on the paleo diet.  Perhaps I’m not as well-read as I thought.  I’ll keep my eyes open for confirmation.

The potential calcium deficiency, I’ve heard of before.  I’m still open-minded on it.  I am starting to wonder if we need as much dietary calcium as the experts tell us.  The main question is whether inadequate calcium intake causes osteoporosis, the bone-thinning condition linked to broken hips and wrists in old ladies.  This is a major problem for Western societies.  Nature hasn’t exerted much selection pressure against osteoporosis because we don’t see most of the fractures until after age 70.  I wouldn’t be surprised if we eventually find that life-long exercise and adequate vitamin D levels are much more important that calcium consumption.

With regards to calcium supplementation, you’ll find several recent scientific references questioning it.  For example, see this, and this, and this, and this, and this.  If you bother to click through and read the articles, you may well conclude there’s no good evidence for calcium supplementation for the general population.  If you’re not going to supplement, would high intake from foods be even more important?  Maybe so, maybe not.  I’m don’t know.

If you check, most of the professional osteoporosis organizations are going to recommend calcium supplements for postmenopausal women, unless dietary calcium intake is fairly high.

If I were a women wanting to avoid osteoporosis, I’d do regular life-long exercise that stressed my bones (weight-bearing and resistance training) and be sure I had adequate vitamin D levels.  And men, you’re not immune to osteoporosis, just less likely to suffer from it.

Insulin Resistance

Insulin resistance from a relatively high-fat diet is theoretically possible.  In reality, it’s not common.  I’ve read plenty of low-carb high-fat diet research reports in people with type 2 diabetes.  Insulin levels and blood glucose levels go down, on average.  That’s not what you’d see with new insulin resistance.  One caveat, however, is that these are nearly all short-term studies, 6-12 weeks long.

If you have diabetes and develop insulin resistance on a high-fat diet, you will see higher blood sugar levels and the need for higher insulin drug doses.  Watch for that if you try the paleo diet.

Are High Total and Saturated Fat Bad?

Regarding relatively high consumption of total and saturated fat as a cause of heart or other vascular disease: I don’t believe that any more.  Click to see why.  If you worry about that issue, choose meats that are leaner (lower in fat) and eat smaller portions.  You could also look at your protein foods—beef, chicken, fish, eggs, offal, etc.—and choose items lower in total and saturated fat.  Consult a dietitian or online resource.  Protein deficiency is rarely, if ever, a problem on paleo diets.

In Conclusion

I think the paleo diet has more healthful potential than realized by the Joslin blogger(s).  I’m sure they’d agree we need more clinical studies of it, involving both type 1 and 2 diabetics.  I appreciate the “heads up” regarding potential vitamin B deficiencies.  My sense is that the Joslin folks are willing to reassess their position based on scientific studies.

I bet some of our paleo-friendly registered dietitians have addressed the potential adverse health issues of the paleo diet.  Try Amy KubalFranziska Spritzler (more low-carb than paleo) or Aglaée Jacob.  I assume the leading paleo diet book authors have done it also.

If you’re worried about adverse blood lipid changes on the paleo diet, get them tested before you start, then after two months of dieting.

Steve Parker, M.D.

PS: The paleo diet is also referred to as the Stone Age diet, caveman diet, Paleolithic diet, hunter-gatherer diet, and ancestral diet.

Do We Need Supplements Because Our Soils Are Depleted?

In my recent review of The Blood Sugar Solution, I noted the numerous supplements recommended by Dr. Mark Hyman: between 11 and 16 supplements.  And one of those supplements is a multivitamin/multimineral supplement that has 20 or so different components.

One reason we need the supplements, according to Dr. Hyman, is because the soils in which we grow food over the years has been depleted of minerals and other basic plant building blocks.

I know one doctor who told his patients the same thing while selling them over-priced supplements straight from his office.

So is there any truth to the “soil depletion” argument for supplements?

Not much, if any, according to Monica Reinagel.  She reviewed the topic in 2010 at her Nutrition Diva blog: http://nutritiondiva.quickanddirtytips.com/are-fruits-and-vegetables-getting-less-nutritious.aspx.  I trust Monica.  In the same article, you’ll find links to her opinion on whether organic vegetables are healthier and worth the cost.

I’ve not done a comprehensive review of the soil depletion issue myself.   It’s quite a difficult area to research; try it and you’ll see.  The Soil Science Society of America, founded in 1936, sounds like a great place to find the answer.  No such luck.

The U.S. is a huge country with lots of different soil types and usage histories.   Soils in one field may be depleted in certain components whereas the field across the road may be quite rich.  Soils are not static.  Farmers are always making amendments to the soil, either with fertilizers or other additives, or by rotating crops.

Wouldn’t you think farmers, whether small family units or huge corporate enterprises, would do what’s necessary to keep their soils productive?

Another way to look at soil depletion would be to look at the nutrient content of the plants and animals that depend on soil for life.  The U.S. Department of Agriculture did that in its 2004 publication, “Nutrient Content of the U.S. Food Suppy, 1909-2000.”  This paper includes 10 vitamins and nine minerals.  For the boring details, see   http://www.cnpp.usda.gov/publications/foodsupply/foodsupply1909-2000.pdf.   Some excerpts:

Levels for most vitamins and minerals were higher in 2000 than in 1909.

Levels for vitamin B12 and potassium were lower in 2000 than in 1909, but over the series, met or exceeded current recommendations for a healthy diet….

The authors attibute lower potassium availability to lower consumption of plant foods, especially fresh potatoes.  I’m increasingly interested in the possibilty that low potassium consumption may contribute to heart disease and premature death.  But that’s a topic for another day.

I’m skeptical about claims of widespread soil depletion in the U.S. as a cause of food supply degradation.  Supplement sellers are sure to disagree.  To be sure you’re getting the nutrients you need, eat a wide variety of foods.

Steve Parker, M.D.

PS: The American Council on Science and Health has a brief article on whether everybody needs a multivitamin/multimineral supplement.

New research is questioning the benefits of taking supplemental vitamins and minerals, suggesting that, for the general population, such supplements may actually pose more risks than benefits.

Click for the full article: http://www.acsh.org/factsfears/newsid.3067/news_detail.asp

PPS:  Oregon State University’s Linus Pauling Institute published a long article on the multivitamin/multimineral supplement issue.  It seems fairly balanced to me.  The Institute notes the 2006 National Institutes of Health assessment that we have insufficient evidence to recommend either for  or against such supplementation (Annals of Internal Medicine, 145(5), 2006: 364-371).  Nevertheless, the Linus Pauling Institute recommends supplementation as “insurance.”  You know, just in case.

Right Diet Preserves Brain Function and Size

mp9004223691.jpgThe journal Neurology reports that the proper diet seems to help prevent age-related brain shrinkage and cognitive decline.

From the press release:

People with diets high in several vitamins or in omega 3 fatty acids are less likely to have the brain shrinkage associated with Alzheimer’s disease than people whose diets are not high in those nutrients, according to a new study published in the December 28, 2011, online issue of Neurology, the medical journal of the American Academy of Neurology.

Those with diets high in omega 3 fatty acids and in vitamins C, D, E and the B vitamins also had higher scores on mental thinking tests than people with diets low in those nutrients. These omega 3 fatty acids and vitamin D are primarily found in fish. The B vitamins and antioxidants C and E are primarily found in fruits and vegetables.

So the dietary pattern linked to preservation of brain size and function in this study is: high omega-3 fatty acids and vitamins B, C, D, and E. I don’t know if study participants were getting these nutrients from supplements or from food or a combination. (I haven’t read the full article.)

To find foods high in the aforementioned nutrients, you can use NutritionData’s Nutrient Search Tool.

Note that the time-honored Mediterranean diet is also associated with lower rates of dementia and slower rate of age-related mental decline.

I previously reported that a supplement cocktail of three B vitamins slowed the rate of brain shrinkage.

Steve Parker, M.D.

Reference: Bowman, G.L., et al. Nutrient biomarker patterns, cognitive function, and MRI measures of brain aging. Neurology. doi: 10.1212/WNL.0b013e3182436598

h/t to Randall Parker at FuturePundit