After more than 20 years as a health professional, my philosophy has remained constant, but I have definitely revised my guidance regarding things like eating low-fat foods, calorie counting and intermittent fasting. In point of fact, some of the guidance I provide to my clients and even the messages I write about in articles are vastly different from what they were five to ten years ago. These revisions are the result of advancing knowledge of human metabolism and physiology rather than indecisiveness. Weight gain has always been caused by mechanisms, but our understanding of how the body processes nutrients and stores them is constantly changing. For example, carbohydrate, protein and fat still have 4, 4 and 9 calories per gram, respectively, but insight into the functions of the gut microbiome and hormones has changed the narrative on the roles of fats and sugars.
Over the years, my understanding of low-fat foods, calorie counting and fasting has evolved. With very few exceptions, I no longer advise my clients to eat low-fat foods, count calories and eat within an hour of waking. Read on to learn why…
“Eat low-fat meals.” Without a doubt, my view of the role of dietary fat has evolved the most. In fact, I believe that as a nation, our early Dietary Guidelines for Americans were incorrect in their recommendations to consume a low-fat diet and, especially, to replace high-fat foods with low-fat and fat-free options. Unfortunately, Americans substituted sugar and highly processed foods for fat as a result of those recommendations. During the past 40+ years (which coincides with when the low-fat guidelines were introduced) the U.S. population has become more overweight and obese.
Instead: Eat whole, unprocessed foods and include healthy fats (omega-3 and monounsaturated) at every meal. A caveat: Fruits and vegetables are “low-fat foods” that are underconsumed by most people, so don’t skimp on these particular low-fat and fat-free foods.
“Count calories and calculate macros.”
Which comes first, calories in or calories out? Simply burning more calories than you consume is all that is required to help you lose weight. I learned this in school and touted this statement for years. However, most people are unable to estimate their portion sizes, meaning that their calorie counts are often unreliable. Most importantly, quality is more important than quantity by an exponential amount. Instead, there is evidence that, regardless of how many calories they contain, ultra-processed foods may have a negative impact on our gut health and, as a result, alter the hormones that control hunger and satiety (ghrelin and leptin, for instance). Thus, it’s time to shift the messaging from counting calories to eating as many whole, unprocessed foods as possible.
Eat as soon as you wake up. I once believed that breakfast was the most important meal of the day and that eating in the morning could jumpstart your metabolism. Now, I’m much less certain about that. Intermittent fasting (IF), also referred to as time-restricted feeding, is currently popular and associated with many health benefits. Although we do know that going 12 to 16 hours without eating will not “slow down metabolism,” I am not entirely convinced that IF is the best strategy for everyone. Instead: When you get hungry, eat. That is, practice intuitive eating (also known as mindful eating). Try different eating and fasting windows because some people may get the alleged benefits of IF with just a 12-hour fast (say, from 7:00 p.m. to 7:00 a.m.). The length of an eating window, however, is still secondary to what someone eats and drinks during that window (see above points regarding the quality of calories consumed).
One final thought As it turns out, I was not really wrong when I gave that advice in the past, and neither were my professors, mentors or colleagues when they taught me that information. We simply promoted nutrition standards based on the information we had at the time. It is important to realize that our understanding of how the body digests and stores carbohydrates, fats, proteins and micronutrients is constantly evolving—and will likely continue to evolve well into the future, so it’s vital that you review emerging research and update the advice you share with your clients accordingly.
