Wouldn't it be awesome to test how you respond to certain types of diets and use the results as an indicator for your long term ability to gain weight? It would essentially tell you how likely you are to to gain weight with a change in diet over the next six months. This could really help us understand the "hard gainer" vs "fat gainer" conundrum.

SuppVersity brings us a review of literature on exactly that. Subjects followed several different protocols in a bomb calorimeter to measure their energy expenditure throughout the protocol. The idea was to predict weight gained based on their responses to the protocol which were as follows:

  • eucaloric reference diet which was 80% of the weight maintaining diet to account for the reduced energy expenditure due to being confined to the metabolic chamber that contained 50% carbohydrates, 30% fats, and 20% proteins

  • fasting trial (FST) in which the subjects sat in the metabolic chamber fasted

  • low-protein diet (LPF) with 51% carbohydrate, 46% fat, 3% protein

  • standard overfeeding diet (SOF) with 50% carbohydrate, 30% fat, 20% protein

  • high-fat, normal-protein overfeeding diet (FNP) with 20% carbohydrate, 60% fat, 20% protein

  • high-carbohydrate, normal-protein overfeeding diet (CNP) with 75% carbohydrate, 5% fat and 20% protein

To be able to assess the long-term weight gain, all participants returned for follow-up visit to the NIH headquarter 6-months after the initial measures.

As you can see the study covered a wide range of diets extending to each extreme of what people may be taking in. The following were found statistically significant for weight gain: higher decrease in EE while fasting, smaller increase in EE during low protein, higher increase in EE during high CHO overfeeding, and higher reliance on fat for fuel during fasting.

The first two make sense, however the increase in EE with overfeeding and reliance on fat during fasting come as a surprise. Personally I would've expected the opposite. This author of the study attributes the overfeeding results to the response to protein restriction. Conversely the fasting results are attributed to the amount of glycogen stores available, which are typically higher in lean individuals.

This is not one of those studies that necessarily changes how you diet, but it gives us a lot of insight into individual difference. Everyone understands the importance of individualization in nutrition. Studies like this are giving us more and more tools to be able to cater to the individual, and are also very interesting. Personally I love being proved wrong, its an opportunity to look at things with a new perspective.

I highly encourage you to read the full article.

With protein response and glycogen stores being the biggest factors, putting on more muscle and leaning out will only help you. We have plenty of supplements that are perfect for you in your journey for the physique and performance your looking for.