it is unclear whether a person’s set point can be changed.
It is quite clear that people’s set points change over their lifetime—great many people are trim in their 20s and then succumb to the middle-age spread in their 40s. Looks like one can make an argument that in many (but not all) people their set points drift upwards as they age, at least until the 60s when some revert to losing weight, and not only muscle mass but fat as well.
The interesting question, of course, is whether one can “reset” one’s set point to what it was in the 20s.
leptin is influenced by caloric surplus/deficit and macronutrient ratios (primarily carbohydrates)
Any comments (or links) on how low-carb diets in general and ketosis in particular affect leptin?
Right, I mean by specific interventions. For example, dieting down to very low body fat and then maintaining it does not appear to increase leptin sensitivity (much) beyond that of a normal-weight person, nor does exercise.
As far as ketosis and leptin goes, This study indicates that carbohydrate overfeeding increases leptin and energy expenditure, while fat overfeeding does not. This suggests that eating carbohydrates naturally causes you to get full, while fat does not, which is inline with research on satiety and macronutrients. (Keep in mind that fructose is not metabolized like a normal carbohydrate and has different effects on leptin and so may not cause the leptin increase or induce satiety.)
This study indicates that ketosis blunts ghrelin release even in a caloric deficit which could be the reason that people on ketogenic diets (or doing intermittent fasts, which is a fat-burning state) report lower hunger levels. In this situation, leptin is lower which probably reduces metabolic rate a bit (probably not hugely significant), but its effect on hunger is probably balanced out by the change in ghrelin.
If you are doing a ketogenic or low carb diet, if you reach a plateau with weight loss, it could be because your leptin is too low. Doing a carb refeed with glucose (which includes starches), but not fructose, could be beneficial.
Interesting. So this implies that lower hunger in calorie-deficit ketosis is due to low ghrelin which more than compensates for lower leptin… And yes, carb refeeds (usually weekly) are a component of many low-carb diets.
It is quite clear that people’s set points change over their lifetime—great many people are trim in their 20s and then succumb to the middle-age spread in their 40s. Looks like one can make an argument that in many (but not all) people their set points drift upwards as they age, at least until the 60s when some revert to losing weight, and not only muscle mass but fat as well.
The interesting question, of course, is whether one can “reset” one’s set point to what it was in the 20s.
Any comments (or links) on how low-carb diets in general and ketosis in particular affect leptin?
Right, I mean by specific interventions. For example, dieting down to very low body fat and then maintaining it does not appear to increase leptin sensitivity (much) beyond that of a normal-weight person, nor does exercise.
As far as ketosis and leptin goes, This study indicates that carbohydrate overfeeding increases leptin and energy expenditure, while fat overfeeding does not. This suggests that eating carbohydrates naturally causes you to get full, while fat does not, which is inline with research on satiety and macronutrients. (Keep in mind that fructose is not metabolized like a normal carbohydrate and has different effects on leptin and so may not cause the leptin increase or induce satiety.)
This study indicates that ketosis blunts ghrelin release even in a caloric deficit which could be the reason that people on ketogenic diets (or doing intermittent fasts, which is a fat-burning state) report lower hunger levels. In this situation, leptin is lower which probably reduces metabolic rate a bit (probably not hugely significant), but its effect on hunger is probably balanced out by the change in ghrelin.
If you are doing a ketogenic or low carb diet, if you reach a plateau with weight loss, it could be because your leptin is too low. Doing a carb refeed with glucose (which includes starches), but not fructose, could be beneficial.
Interesting. So this implies that lower hunger in calorie-deficit ketosis is due to low ghrelin which more than compensates for lower leptin… And yes, carb refeeds (usually weekly) are a component of many low-carb diets.