Dieter’s Sleep Better with High Protein
Just about every bodybuilder has heard that whey protein can enhance weight loss, but get ready for some exciting news, dieters taking high protein also sleep better. Before we get into the new sleep studies, let examine the research regarding whey protein and weight loss.
Whey Protein and Fat Loss
Acute studies have reported that whey protein isolate (60 grams per day) evaluated over six months resulted in greater weight loss also resulted in lower cortisol levels (lean muscle preservation) and increased ghrelin release (satiety enhancement). A previous study published in Nutrition & Metabolism reported that people on whey protein supplementation lost more weight than a control group receiving maltodextrins in conjunction with a calorie-restricted diet. Each subject was instructed to consume one supplement 20 minutes before breakfast and one supplement 20 minutes before dinner. The whey protein supplement contained 10 grams of protein per serving as a combination of intact whey protein and peptides. It also contained minerals that were purified from milk. The control group received an isocaloric beverage containing maltodextrin. After 12 weeks, weight loss was consistently higher in the whey protein subjects, primarily the result of losing body fat (subjects taking whey protein lost 6.1 percent of their body fat mass). The whey protein group subjects also lost significantly less lean muscle mass compared to control subjects. Whey protein may be the perfect fat-loss supplement when dieting for an important event or for targeting fat loss while maintaining lean muscle. Since whey is nutrient dense but relatively low in energy (~4 kcal/g), supplementation is an efficient method to promote skeletal muscle anabolism while promoting catabolism in fat cells and, therefore, is hypothesized to improve both muscle growth and fat loss.
Whey Protein May Enhance Metabolism
More exciting news was recently reported that whey protein taken before exercise can rev up your fat metabolism. To determine whether whey protein supplementation taken before an acute bout of heavy resistance training would influence postexercise resting energy expenditure and fat oxidation. Eight resistance-trained subjects participated in a double-blind two-trial crossover design, where resting energy expenditure and fat oxidation were measured at 7:00 a.m. on four consecutive days. On the second day of trial 1, subjects consumed either whey protein (18 g of whey protein, 2 g of carbohydrate, 1.5 g of fat) or carbohydrates (1 g of whey protein, 19 g of carbohydrate, 1 g of fat) 20 min before a single bout of heavy resistance exercise (nine exercises, 4 sets, 70%-75% 1-repetition maximum). Resting energy expenditure and fat metabolism were measured 24 and 48 h after heavy resistance exercise. During trial 2, the same protocol was followed except subjects consumed the carbohydrate supplement before heavy resistance exercise. Compared with baseline, REE was elevated significantly in both carbohydrate and protein at 24 and 48 hours after heavy resistance exercise. At 24 hours after heavy resistance exercise, resting energy expenditure in response to whey protein was significantly greater compared with carbohydrate. Fat oxidation increased significantly in both carbohydrate and whey protein group at 24 hours after heavy resistance exercise compared with baseline. No differences were observed in total energy intake, macronutrient intake, or heavy resistance exercise volume. Timing whey protein before heavy resistance exercise may be a simple and effective strategy to increase energy expenditure by elevating resting energy expenditure the day after heavy resistance exercise. Increasing resting energy expenditure could facilitate reductions in body fat mass and improve body composition if nutritional intake is stable. The newest research also suggests that dieting athletes sleep better with higher protein diets, which was recently published in the American Journal of Clinical Nutrition.
Higher Protein Enhances Sleep
Most studies have suggested that a high carbohydrate dinner before bed will enhance sleep due to the increased insulin and tryptophan levels. This implies greater synthesis of serotonin and melatonin and, thus, better sleep. In contrast, a recent pilot study found that subject’s consuming more dietary protein resulted in better sleep after four weeks of weight loss. A new study set out to examine the impact of high protein diets, weight loss, and its effect on sleep duration. Then, in the main study, 44 overweight or obese participants were included to consume either:
-a normal-protein or
-a higher-protein weight loss diet.
After three weeks of adapting to the diet, the groups consumed either 0.8 or 1.5 kilograms of protein for each kg of body weight daily for 16 weeks. The participants completed a survey to rate the quality of their sleep every month throughout the study. Those who consumed more protein while losing weight reported an improvement in sleep quality after three and four months of dietary intervention. The researchers thought that the mechanism of the effect of protein on sleep after acute feeding may be related to the synthesis of brain neurotransmitters (serotonin, melatonin, and dopamine). Additionally, whey protein has an added advantage for sleep in that whey-derived a-lactalbumin was suggested to improve sleep quality or related outcomes in both animals and humans because of its high content of Tryptophan. In conclusion, the consumption of a greater proportion of energy from protein while dieting may improve sleep in overweight and obese adults.