A couple of months ago, I wrote a blog post entitled, Why Are Many Dietitians So Critical of Low-Carbohydrate Diets? Subsequently, someone asked me if I thought dietitians were more bothered by the low carb or high fat aspect of a carbohydrate-restricted diet. I said it would really depend on the RD, but because most have been trained and therefore believe that that the brain needs a minimum of 130 grams of carbohydrates per day to function, that would probably be the primary concern. However, I'm starting to rethink that answer, particularly with respect to saturated fat.
My friend and fellow RD and CDE Aglaee Jacob wrote a wonderful article for this month's issue of Today's Dietitian entitled "Coconut Oil: Learn More About this Superfood that Contains Healthful Saturated Fats." In it, she outlines the many benefits of coconut's medium-chain triglycerides (MCTs) on neurological health, weight, and cardiovascular disease, among other issues. Aglaee previously wrote an article for the same publication on carbohydrate restriction for diabetes management which didn't prompt much of a response from their readership (although her previous article about a high-fat elimination protocol for gut health didn't sit well with one RD). Apparently, characterizing coconut oil as a "superfood" and explaining the benefits of saturated fats went a little too far for many other dietitians. Aglaee received a message from the Today's Dietitian editor informing her that many RDs were upset by her article, particularly her assertion that saturated fats are not associated with heart disease. The editors are allowing her to publish a response, although they are uneasy about the extent of the criticism. Several other progressive RDs and I have written the editor in support of Aglaee's article and her position, along with providing supporting literature on saturated fats, and I'm confident that her published response will be as clear and convincing as the previous one defending her approach to gut health.
I find it concerning that saturated fats and trans fats are repeatedly lumped together as "bad fats," when their properties and effects on health are very different. The former are natural and most are healthy, depending on the chain length and type, and have been consumed by human beings for thousands of years. Trans fats, on the other hand, are highly processed, inflammatory, cause unfavorable changes to serum lipids, and frankly our bodies don't know how to deal with them. Unfortunately, many dietitians believe saturated fat contributes to heart disease and must be minimized, if not avoided altogether, despite the lack of evidence in this regard.
It's interesting that Today's Dietitian -- a publication I read and enjoy, as it often provides a lot of great information for RDs -- recently offered a guide from SCAN (Sports, Cardiovascular And Wellness Nutrition Dietetic Practice Group of the Academy of Nutrition & Dietetics) entitled 10 Simple Steps to Make Good Nutrition More Delicious, yet very few dietitians took issue with the fact that this resource is funded by a grant from the makers of Country Crock and I Can't Believe It's Not Butter! margarines. Although these margarines no longer contain trans fats, they do contain interesterified fats, which are highly processed and, according to early research, may be just as problematic. Natural fats like butter and coconut oil should be discouraged, and we as RDs are supposed to promote these manufacturated fats instead? This doesn't make sense to me.
For the record, while I'm disappointed in some of the corporate sponsors of Today's Dietitian, I truly appreciate their publishing of Aglaee's forward-thinking articles despite the controversy they ignite. I believe they strive for a balanced approach that will appeal to a broad range of nutrition professionals, which is laudable given the recommendations that come from many of the major health organizations.
When I see dietitians writing columns about low-carb recipes , the overwhelming majority are promoting foods that are low in both carbohydrates and fat. I'm very happy that some are willing to offer meal planning ideas that limit grains or starches, but the fat content is often unnecessarily low. Egg whites, low-fat cheese, and extra-lean turkey figure prominently in the low-carb recipes I've seen from dietitians online. I will agree that certain people with familial hypercholesterolemia, a relatively rare condition, may need to limit fat intake. Also, for individuals consuming a high-carbohydrate diet, cutting back on saturated fat may be wise. But on a carbohydrate-restricted diet, fat is required as the primary energy source, with saturated and monounsaturated fats being the preferred forms for this purpose. There is a limited amount of protein the body can use effectively, and a very-high-protein, low-carbohydrate, low-fat diet is unsustainable and unhealthy.
I propose that it's time to stop the fat phobia and encourage our patients and clients to eat natural sources of saturated, monounsaturated, and (in smaller quantities) certain polyunsaturated fats in order to optimize rather than jeopardize their health with processed fats that have known and unknown adverse side effects. And the "natural" list includes coconut oil, for all the reasons so eloquently stated by Aglaee in her article.
1. Siri-Tarino P, et al. Meta-analysis of prospective cohort studies evaluating the association of saturated fat with cardiovascular disease. Am J Clin Nutr 91:535–546, 2010
2. Lawrence G. Dietary fats and health: dietary recommendations in the context of scientific evidence. Adv Nutr 1;4(3):294-302, 2013
3. Sundram K, et al. Stearic acid-rich interesterified fat and trans-rich fat raise the LDL/HDL ratio and plasma glucose relative to palm olein in humans. Nutr Metab (Lond)15;4:3, 2007
Franziska Spritzler, RD, CDE