The parts of your body that aren’t fat tissue are collectively called fat-free mass or lean mass. Fat-free mass includes muscle, organs, bones, water, connective tissue, etc. Reduced-calorie diets are often linked to reduction of body components—like muscle—other than the desired loss of excess fat.
One proven effective way to preserve muscle mass on a reduced-calorie diet is to consume adequate protein. Judicious exercise also helps.
I haven’t read the full article below, and probably won’t. For what it’s worth, the authors say fat-free mass can be preserved during a very low-carb ketogenic diet via adequate intake of vitamin D, leucine, and whey protein. Do you think maybe they’re selling a particular supplement?
The abstract isn’t very well written. Or is it the title that’s misleading?
The loss of fat free mass (FFM) that occurs during a weight loss secondary to low-calorie diet can lead to numerous and deleterious consequences. We performed a review in order to evaluate the till-now evidence regarding the optimum treatment for maintaining FFM during low-calorie diet. This review included eligible studies. In order to maintain FFM during a low-calorie diet, there are various diet strategies: adopt a very-low carbohydrates ketogenic diets (VLCKD) and take an adequate amount of specific nutrients (vitamin D, leucine, whey protein). As regard the numerous and various low-calorie diet proposals for achieving weight loss, the comparison of VLCKD with prudent low-calorie diet demonstrated that FFM was practically unaffected by VLCKD. This is possible for numerous mechanisms, involving insulin and insulin like grow factor-I – growth hormone (IGF-I-GH) axis, and which acts by stimulating protein synthesis. Considering protein and amino acids intake, an adequate daily intake of leucine (4 grams/day), and whey protein (20 grams/day) is recommended.
Regarding vitamin D, if the blood vitamin D has low values (<30 ng/ml), it is mandatory that an adequate supplementation is provided, specifically calcifediol because in the obese subject, this form is recommended to avoid seizure in the adipose tissue: 3–4 drops/day or 20–30 drops/week of calcifediol are generally adequate to restore normal 25(OH)D plasma levels in obese subjects.
I had never heard of that obesity-calcifidiol connection.
Steve Parker, M.D.