The Surprising Truth About Low Carb Diets: Why Quality Matters for Weight Loss

Does Quality Matter in Low Carb Diets?  – Nancy’s Nourishing Nuggets

 Weight loss and low carb diets…. the information is so confusing! Researchers from Harvard’s Chan School of Public Health recently published an analysis of the association between low carbohydrate diets (LCDs) and long-term weight control, with a special focus on diet quality. The analysis included 3 well-described prospective research studies which included the Nurses’ Health Study (NHS) of which I have been a participant now for 40+ years, so this information got my attention. It also supports what I have been saying to my patients about food quality and weight management for many years! The other 2 studies that were reviewed included the Nurses’ Health Study II (NHSII), and the Health Professionals Follow-up Study (HPFS), with over 123,000 total participants with a mean age of 45. The main area of focus was self-reported weight change over a 4-year period, and how this related to several indicators of a low carb diet, including total carbohydrate intake, but also the proportion of the diet comprised of plant versus animal protein / fat, as well as the amount of refined compared to more healthful carbohydrates.

The overall carbohydrate intake was higher after 4 years in these studies than in previously published randomized trials, which was approximately 40% versus the 34% which was reported after 1 year on a LCD and of course demonstrates the real -world ability to maintain a low carb diet over a long period of time. However, the focus on diet quality indicated that LCDs that emphasized healthy plant-based foods were linked to less weight gain. In contrast, low carb diets that emphasized animal-based proteins and fats, as well as those with a higher proportion of refined carbohydrates, were associated with more weight gain. This makes sense since many populations that live fit and healthy into their 9th or 10th decade (Blue Zones) do not avoid carbs – they include legumes, sourdough breads and even some pasta into their diets! I always tell my patients it is all about balance! So just focusing on macronutrients alone may not be enough to get you to your weight loss goals and to maintain them, the quality of your food is even more important – as I always say eat the rainbow and that doesn’t mean M&M’s or Skittles!