How to Halt or Even Reverse Weight Gain as You Age

Let’s say you and your 20-something son meet up for breakfast. You both order a couple of eggs, a slice of whole-wheat toast and coffee. You both enjoy the same breakfast. But in the coming hours, your bodies are going to respond to this meal very differently. These differences explain why we gain weight as we age and, more important, how we can reverse that process, prevent age-related weight gain and give ourselves a “whole body reset.”

The metabolism myth

We used to assume that the reason we gained weight in midlife was because of a decline in metabolism — or more precisely, what scientists call resting metabolic rate (RMR), which is how much energy your body needs to carry on basic functions. But a shocking study published in the journal Science in August 2021 found that our individual cells rev at pretty much the same rate in our 40s and 50s as they did in our 20s — indeed, our metabolic rate doesn’t start to slow until about age 60 or so, when it begins to drop at a rate of .07 percent a year.

So the growing girth you notice — the difference between your body now and your body when you were in your 20s — isn’t due to metabolism. Something else is at play. Something you can actually control.

Different ages, different muscles

A 20-something body utilizes the protein from breakfast — 12 or so grams from the eggs and 4.5 grams from the whole-wheat toast — with maximum efficiency, turning the protein into healthy new muscle cells. This whole process is known as protein synthesis.

But while this life-sustaining process is going on inside your son’s body, it actually hasn’t kicked into gear inside yours. Studies show that older adults need at least 25 to 30 grams of protein at a time to stimulate the same muscle-building process that a younger person can get from just a couple of eggs.

Here’s why that’s important: The human body is constantly breaking down and building up muscle. But when the destruction of muscle outstrips its rate of repair over the long term, that eventually leads to a loss of muscle tissue. Studies show that older folks who fail to get 25 to 30 grams of protein in the morning are likely to stay in muscle-loss mode all day. At some point between ages 30 and 40, adults begin to lose 3 percent to 8 percent of their muscle mass each decade.

And the less muscle we have, the more fat we gain: Muscle not only burns more calories, but it helps to control blood sugar. The less muscle you have, the higher your blood sugar — and the more of that blood sugar your body is forced to turn into fat. Muscle loss has also been linked to increased risk of diabetes, cancer, heart disease, Alzheimer’s and a compromised immune system.