How Your Weight Impacts Your Longevity (and Why Drugs Might Not Be The Answer)

Excess weight or body fat is an issue that millions of Americans are dealing with—and the potential adverse health effects are not insubstantial, especially when the excess weight is in tandem with metabolic dysfunction. 

If you’re trying to lose weight, it can be tempting to jump on the weight loss drug train—after all, if all of the celebrities are on them, why shouldn’t you? While medications like semaglutide undoubtedly have a time and a place—especially for people who have been trying unsuccessfully to lose weight or manage their blood sugar for a very long time—there are significant downsides to consider.

In this article, we’ll explore the top ways that excess weight impacts health and longevity, plus some reasons why weight loss drugs may not be the consequence-free magic bullet you’ve been looking for.

Excess Weight and Longevity

Excess body weight is linked to several aspects of aging, including increased inflammatory markers, impaired immunity, and mitochondrial dysfunction. Research has shown that being obese or severely obese reduces lifespan by up to 7.6 years in men and up to 10.3 years in women. 

Similarly, a 2018 study found that American adults who were classified as obese had a 27% increased risk of dying during the 24-year-long study, with the severely obese participants almost doubling their risk of premature mortality. In addition to causing reduced life expectancies, obesity is associated with a markedly increased risk of developing other chronic diseases that can lead to premature mortality, including those related to cardiovascular, metabolic, and cognitive dysfunction. 

Excess weight can also affect biomarkers of longevity, like telomeres. These are the protective endcaps of our chromosomes that are shortened during the aging process and act as proxies for biological age. One study found that older adults with higher body fat were more likely to have shorter telomeres. 

NAD+, a coenzyme needed for metabolism and DNA repair, declines during aging and in people with excess body fat. Being obese or having excess body fat may accelerate the aging process by further reducing NAD+ levels. 

However, it’s important to note that being underweight is also linked to shorter lifespans, mortality, and increased frailty with age, so maintaining a healthy body weight for your frame is ideal.

Excess Weight and Cardiometabolic Health

The effects of excess weight are seen in various cardiovascular or metabolic conditions and symptoms, including altered glucose metabolism, abnormal lipid levels, and elevated blood pressure.

Even in people who were found to be “metabolically healthy,”  being overweight or obese was still an independent risk factor for developing cardiovascular conditions in a 12-year study of 520,000 people.

Another study published in the Lancet found that each 5-point (kg/m2) increase in BMI (Body Mass Index) was associated with a 27% increase in cardiovascular conditions. To put that in perspective, a 5-point increase in BMI would move you up a “class,” as a BMI of 24 is “healthy,” but a BMI of 29 is considered overweight. 

The reasons for this correlation are multifactorial. However, one theory is that an accumulation of adipose (fat) tissue in the myocardium (heart muscle) alters cardiovascular structure and function, and hormones secreted by adipose tissue create a highly inflammatory state.

Similarly, excess body fat is linked to metabolic dysfunction and impaired glucose metabolism. Research published in JAMA Network Open concluded that each one-point increase in BMI increased the odds of a common metabolic disorder by 67%. The main driver behind this connection is that excess adiposity causes alterations in β-cell function (cells in the pancreas that secrete insulin), leading to impaired insulin signaling and increased blood sugar.

Excess Weight and Brain Health

More and more research is emerging showing the link between cognitive dysfunction and excess body fat or weight. 

The strongest association between excess weight and cognitive loss occurs when an individual is obese at mid-life. As mentioned, avoiding being underweight in later life may actually have a protective effect on health. 

A 28-year follow-up study confirmed that conclusion. Published in 2018, the Whitehall II Study followed over 10,000 adults and found that being obese at age 50—but not at age 60 or 70—was linked to an increased risk of cognitive loss 28 years later. 

This may be because excess adiposity releases pro-inflammatory cytokines and proteins, causing cerebrovascular and neuronal damage. 

Should You Take Weight Loss Drugs?

While only you and your doctor can answer this question, there are some things to consider when thinking about taking a weight loss medication like semaglutide. 

First things first: how does semaglutide work? 

Semaglutide is a medication that mimics a naturally occurring hormone called glucagon-like peptide-1 (GLP-1). Responsible for numerous vital aspects of metabolism, GLP-1 inhibits caloric intake by acting on the brain’s appetite centers and slowing down gastric emptying—the speed at which food moves from the stomach through the rest of the gastrointestinal tract. With slower gastric emptying, food remains in the stomach longer, leading to feelings of fullness and reduced caloric intake. Therefore, semaglutide is known as a GLP-1 agonist because it mimics these effects.

Semaglutide has been shown to produce significant weight loss. One landmark study found that those who used the medication once a week for over a year had a 14.9% reduction in body weight compared to 2.4% in the placebo group. However, those in the semaglutide group also experienced side effects such as nausea, vomiting, diarrhea, and other gastrointestinal symptoms.

However, research is also emerging that people experience significant weight regain after stopping the drug—and with costs upward of $10,000 per year, most people cannot afford to keep taking it forever. One study found that one year after stopping semaglutide, people regained two-thirds of the weight they had lost while on the drug.

Plus, the type of weight lost while on semaglutide is not all body fat. People tend to lose a lot of muscle mass—and when the weight comes back, the muscle does not. As muscle mass is critical for healthy aging and longevity, the potential benefits of weight loss may not be worth it unless in extreme cases. 

Your Takeaways

Having a bit of excess body weight is not always a bad thing—especially if you are an older adult, are metabolically healthy, or have a history of being underweight. However, becoming obese or severely obese has significant health effects that have been thoroughly researched. 

Some leading health effects of too much body weight or fat (adiposity) include lower life expectancy, accelerated biological age, and an increased risk of cardiovascular, metabolic, and cognitive dysfunction. 

While it can be tempting to take weight loss medications like semaglutide, they have both minor side effects (like nausea) and significant ones (like muscle loss) that need to be discussed with a qualified healthcare practitioner. While weight loss drugs are not wrong for everybody, they also are not right for everybody. 

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