Low-Fat or Low-Carb?

alyzahk |

ThumbnailDr Bob Explains Series on Financial Topics





Health enthusiasts these days follow either a low-carb or low-fat diet. It turns out that both may be wrong. Consuming less fat, carbs, or protein may be the wrong way to think about healthy eating. 8 out of 10 of us are confused by advice about healthy eating. Take fat, for example. Advice against fat began to enter mainstream thinking in the 1970s. Less fat was supposed to protect against cardiovascular and other diet-related chronic diseases. In the decades since, this teaching became nutritional canon. When I was a kid  in the 60s, there was one undifferentiated category of “milk.” Today’s dairy sections are overtaken by 0%-, 1%-, 2%-, and other low-fat options.

Macronutrients consist of fat, protein, and carbs, so less fat consumption automatically means eating more carbs and/or protein. (Imagine a pie chart.) Since the 1970s, carbs have filled the gap left by fat. (The “low-fat” and “fat-free” labels on foods became so pervasive that I expected my broccoli to be labeled fat-free too!) Unfortunately, the shift towards consuming less fat and more carbs included all kinds of carbs, including highly processed carbs. Small wonder, then, that despite the health claims of low-fat plans, obesity and diabetes have continued to rise. Recently, low-carb diets have become popular. The ketogenic low-carb diet, for example, can draw as much as 70% of caloric intake from fat. Observers found that 50% of youngsters with epilepsy experienced fewer seizures following such a diet. But what is the science behind a low-carb diet? For that matter, what is the science behind the 40-year-old, low-fat advice?

Acknowledging the broad confusion, a group of nutritional scientists from diverse perspectives have taken a stab at identifying common ground. They came up with the following, in part.

  • Whether low-fat or low-carb is the wrong question, and wrong answer. Put another way, the relative proportions of fat and carbs have little health significance.
  • Focus on nutrient quality. Not all fat, for example, is harmful. Trans fats are, but naturally occurring mono- and poly-unsaturated fats can have health benefits.
  • Similarly, highly processed carbs are unhealthy. But unprocessed carbs such as nonstarchy vegetables, whole fruits, legumes, and whole grains are beneficial.
  • Those who suffer from insulin resistance, glucose intolerance and other conditions may indeed benefit from a lower-carb, higher-fat diet.
  • A low-carb diet, even when appropriate, doesn’t necessitate large amounts of protein or animal-based foods. Nuts, seeds, avocados, and other high-fat, plant-based foods are more sensible.

Are these the final word on fat and carbs? Perhaps not. Because of cost, powerful stakeholders, and other factors, nutrition studies often fall short of research standards that preserve objectivity and explain causality. Still, identifying common ground as one group of scientists has done is a promising step forward.

If you accept that health affects finances, then you probably agree that healthy eating can shape financial planning. Unfortunately discerning sound nutrition research requires a trained eye. Seek advice from those who have it and are relatively free of self-interested biases.

Disclosure: This commentary is furnished for the use of Glen Eagle Advisors and its clients. It does not constitute the provision of investment advice to any person. It is not prepared with respect to the specific objectives, financial situation or particular needs of any specific person. Investors reading this commentary should consult with their Glen Eagle Advisors representative regarding the appropriateness of investing in any securities or adapting any investment strategies discussed or recommended in this commentary. The Chartered Financial Analyst (CFA) designation is conferred by the CFA Institute.