|You always crave the foods you must not eat, right? No, ... a recent study finds decreases in sweet and starch cravings in obese individuals on low-carb diets.|
The reason? No, still no "metabolic advantage": reduced hunger and food cravings and the subsequently increased adherence and reduced energy intake - an assumption that isn't proven, but at least supported by Colette Heimowitz' latest paper. A paper based on a study that was sponsored by Atkins Nutritionals and smells of bias, but a study that's in line with millions of N=1 reports on the internet.
As the authors explain, "[...m]any individuals entering weight loss programs may believe that restriction of a certain type of food (e.g., carbohydrate, CHO) may increase their cravings for that food" (Heimowitz 2017). With their vested interest in making the low-carb diet and their low-carb convenience food look good, the scientists' goal was to prove that these carbohydrate cravings don't exist. Obviously, that's not what you will read in the paper which phrases things significantly less suspiciously stating that "the present study was to assess motivation for entry into a weight loss program, acceptability of low-CHO commercially-prepared foods, and changes in food cravings during rapid weight loss associated with high-fat, low-CHO dietary consumption" (Heimowitz 2017). "The foods provided for the first 2 wks included Atkin’s products (frozen dinners, bars and shakes), and some freshly-prepared meals (total fat was 54±4% of energy (%E), protein, 28±2 %E, and CHO 14±1 %E; fiber intake, 26±8 g/d) and resulted in an energy deficit of 1198 ± 655 kcal/d, then...
All N=20 subjects (10 men and 10 women with a mean age o 40±8y, and a BMI in the red obesity zone of 34±3 kg/m²) completed the study with their main goal being to look better - not to be healthier, which ran as a poor second, along with family issues.
"[f]or the next 2 wks, subjects prepared their own meals with the goal of achieving a similar food intake. Subjects were surveyed regarding reasons for enrolling in the program, and at baseline (BL) and 4 wks, completed the Food Craving Inventory (cravings for foods that were fatty, sweet, high in CHO (starches), or categorized as fast foods), and the Three Factor Eating Questionnaire (TFEQ) to assess food intake motivation" (Heimowitz 2017).
Figure 1: Macronutrient composition of the energy-reduced diets (intended deficit of ~1200kcal/day | Heimowitz 2017)
|Figure 2: Plot of the most relevant anthropological and psychological study outcomes (Heimowitz 2017).|
- 95% of subjects reported being somewhat satisfied to very satisfied with the meals,
- 60% felt less hunger after meals, and
- 75% reported reduced 'eating when bored'
What is particularly interesting is that the reduction in sweet cravings tended to be associated with a reduction with significant reductions in disinhibition and increases in cognitive restrained: over time, the subjects were thus more and more able to control their food intake and less susceptible to fall victim to their (now reduced) cravings - reduced cravings for sweets and starches and reduced cravings for fatty foods (11±7% | P<0.03) and fast food cravings (19±5% | P=0.0006), all without the often-heard-of difference between men and women (you know how women are supposed to crave sweets, and men fatty foods).
- Brehm, Bonnie J., et al. "A randomized trial comparing a very low carbohydrate diet and a calorie-restricted low fat diet on body weight and cardiovascular risk factors in healthy women." The Journal of Clinical Endocrinology & Metabolism 88.4 (2003): 1617-1623.
- Heimowitz, Colette, et al. "Changes in Food Cravings during Dietary Carbohydrate-restriction." The FASEB Journal 31.1 Supplement (2017): 643-23.