What Is an Ideal Weight for Health? It’s Complicated.
“My weight had been up and down my entire life, but at that time , I was in a particularly bad place. I couldn’t even climb stairs. My blood pressure and blood work were fine, but I had back and knee problems and a lot of pain in all my joints. I had four kids, and I couldn’t do anything with them. I was miserable,” he recalls.
So he stepped on. “It said 204kg,” recalls Allar, who is 1.78m tall. “I had to do something.”
He started the keto diet and lost 68kg in the first year. As general activity became easier, he got on a bike that his daughter (former professional cyclist Erica Carney) and son-in-law (coach Jame Carney) had set up for him in the garage. “I always liked riding a bike, but it was intimidating to start again. When I first got on, I could only go five minutes, but I kept getting on it.”
Eventually five minutes turned into hours outside—two to three in a local park during the week and four to six on the weekends. Within a couple of years, Allar’s weight was under 90kg.
He bounced up and down in the years that followed as he established new habits, but now he’s settled into a routine of recording what he eats, hitting the gym three days a week, and doing long rides—up to 100km on his favorite rail trail—on the weekend. He eats lots of vegetables, stays away from flour and sugar, and keeps his weight around that 90 mark.
He’s happy, fit, and healthy. Even though Allar would technically be categorized as “overweight” on the body mass index (BMI) charts, he has landed on what some experts would define as his “best weight” or ideal weight, the weight that your body settles into while living the healthiest lifestyle you can truly enjoy.
It’s a concept that is gaining traction, as science and society come to realize that there’s a whole lot more to being healthy and fit than the number on a scale. To understand why, let’s take a look at how we got here.
The Mixed Science of BMI
For the past 30 years, health care professionals have used BMI—a measure of how much mass someone has relative to their height—to identify if a person is at a healthy weight. A BMI between 18.5 and 24.99 is considered normal; 25 to 29.9 is overweight; and 30 and above is obese.
But research (and there is a lot of research) has shown that a “normal” BMI rating doesn’t always mean healthy, and an “obese” BMI rating doesn’t always mean unhealthy.
In one 2016 study published in the International Journal of Obesity, researchers from UCLA pulled data from 40 420 people in the latest National Health and Nutrition Examination Survey and analysed the link between BMI and key health markers including blood pressure, glucose, insulin resistance, and cholesterol and triglyceride levels. They found that nearly half of overweight men and women and 29 percent of obese people were otherwise totally healthy. On the flip side, more than 30 percent of those with normal BMIs were actually unhealthy according to those markers.
As a counterpoint, a study of nearly 300 000 people published in 2018 in the European Health Journal drew a fairly direct connection between BMI and disease, stating that the risk of heart attacks, strokes, and high blood pressure increases as BMI increases beyond about 22 to 23.
And then there’s a massive review of 97 studies including 2.88 million people published in 2013 in the Journal of the American Medical Association that reported that though BMIs over 35 were associated with an increased risk of dying from any cause, people with a BMI between 30 and 35 (categorized as “Grade 1 obesity”) had no increased mortality risk, and those who fell into the “overweight” BMI category actually had the lowest risk of dying from any cause.
So yeah, it’s complicated.
BMI—which is calculated by dividing a person’s weight in kilograms by the person’s height in meters squared—can be especially difficult to apply properly to active people like cyclists, who tend to have a higher proportion of muscle tissue, which is denser than fat tissue, and can make someone’s weight relatively heavier for their size.
“Someone like The Rock might have a high BMI [he in fact does, it’s been reported to be 34], but be very healthy,” says Lissette Cespedes, M.P.H., M.D., assistant professor of medicine and endocrinology at Rutgers New Jersey Medical School in Newark, New Jersey.
Excess fat may not raise the risk of mortality per se, overtime, it does raise your risk for those other diseases.
BMI also says nothing about how fat is distributed. Two people may have identical BMI measurements (“normal” or otherwise), but one might store most of their fat as deep abdominal, visceral fat—which is known to be a higher health risk—while the other might store it evenly throughout the entire body as relatively innocuous subcutaneous fat (the kind you pinch under your skin).
To be clear, research is conclusive that excess body fat, especially the type that sits deep in the abdomen, can cause inflammation in the body and is among the factors that can increase your risk for diseases such as cancer, heart disease, and diabetes, among others. Also, though excess fat may not raise the risk of mortality per se, overtime, it does raise your risk for those other diseases, Cespedes says.
That said, there is certainly no one ideal weight or body size that is the perfect portrait of health, says Deborah Horn, D.O., M.P.H., clinical assistant professor, McGovern Medical School at UTHealth in Houston.
“A marathon runner can be extremely lean and still have high blood pressure; there are other mechanisms at work there,” Horn says. “Obesity is the same. Just because you don’t have diabetes, high blood pressure, or abnormal blood pressure and you can ride 100 miles on your bike doesn’t mean the disease of obesity doesn’t exist in your body.”
Horn also makes the distinction that obesity as it is medically defined as a disease (not just a number on the scale), is about “physiology, not fault,” and our genetics are a major factor.
“There hasn’t been a huge genetic shift in the past 30 years, but our genetics respond to our environment, which has changed a lot,” Horn says. “When you team your genetics with environmental stimuli, it changes how your genes express themselves. What we see now is increased risk in the fetal environment that humans develop in that can put you at risk before you’re even out of the womb.”
Diet and Exercise Are Not the Whole Story
Contrary to entrenched conventional wisdom—and what anyone who is very active and eats a healthy diet but isn’t lean can tell you—just because you eat well and exercise lots does not automatically mean you’ll lose or maintain weight. Some people do. Others do not.
“Some people can eat fast food all day long, and their gene pool allows them to do that without driving their weight up, though it’s not otherwise good for them,” Horn says. “Some people will eat very healthy and not large amounts, and their genes give them excellent storage mechanisms,” Horn says.
We are hardwired to survive famines, not lose weight.
We have hormones that make us feel hungry and hormones that make us feel full. When we eat less to try to lose weight, they flip to push us back to where we were, Horn says.
“And as soon as you lose weight, your metabolism goes down by an average of 15 percent, and in some people more,” Horn says. Worse: Even if you regain weight, your metabolism may never completely recover.
We are hardwired to survive famines, not lose weight.
That is not to say weight loss is impossible. Of course, many people can lose or maintain weight loss through lifestyle changes. But for some, it’s a lifelong struggle. And for those who have health reasons to lose weight, medications and (when needed) surgery can trick Mother Nature and help achieve those goals, Horn says.
In the end, the message is the same for everyone regardless of weight: Eat well, move your body, and find a doctor who will work with you to keep tabs on your health and address your personal concerns.
“Bodies come in all shapes and sizes and health can look like a lot of different things,” Horn says.
Why Fitness Really Matters at Any Size
Having a normal BMI does not make you inherently any healthier than having a BMI (or body composition) in the obese category if you’re not physically fit. In fact, you may be worse off.
No one knows this better than longtime exercise and obesity researcher Steven Blair, P.E.D, a self-described “fat guy” despite eating a healthy diet and being an avid runner—Blair ran every day for more than 30 years and covered about 70,000 miles—throughout his adult life.
Blair, a distinguished professor emeritus at University of South Carolina, has spent decades following tens of thousands of people to see who gets sick, who stays healthy, who lives a long time, and who dies early.
“Obese people who are moderately fit have a death rate one half that of normal weight people who are unfit,” Blair says. “I’m not arguing against getting to a ‘normal’ weight. But I think rather than focusing on BMI, we should focus on healthy behaviors, especially physical activity.”
That’s why exercise physiologists like Brian Housle at the Duke Diet & Fitness Center encourage setting fitness goals, rather than just weight goals.
“We encourage people to focus on improving their peak exercise capacity, or MET peak,” Housle says, “because studies almost unanimously show that high fitness reduces cardiovascular risk regardless of weight.”
One “metabolic equivalent” or MET is the amount of oxygen you use just hanging out on the sofa watching Netflix. Any amount of exercise you do over that increases your MET demand. The highest MET level you can hit is your MET peak.
“When you look at research, around 7.5 METs is the point where weight really had no impact on cardiovascular mortality,” Housle says. “People with BMIs over 30 were no more likely to have heart disease-related mortality than people with a BMI below 25.”
For reference, moderate cycling (a.k.a. riding at about a 15-20km/h pace) is categorized as an 8 MET activity according to the scientific Adult Compendium of Physical Activities, which assigns MET intensities to nearly every physical activity. Lots of cyclists—of all sizes—already accomplish that.
“The important thing is that people don’t view their size as a barrier to being active,” Housle says. “Many people are self-conscious because of how society views them.”
That’s a big problem, says Christy Greenleaf, Ph.D., co-director of University of Wisconsin-Milwaukee (UWM) Body Weight and Shape Research Lab.
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“In the sport and physical activity domain, a lean-looking body is assumed to be a fit athletic body achieved through hard work, self-control, and clean eating,” Greenleaf says. “Bodies that appear to be fat or larger than a socially-idealised size are assumed to be unfit and are the result of laziness and gluttony. That’s not reality.”
“The reality is that people of all shapes and sizes vary in health status, and we cannot accurately evaluate someone’s health or athletic ability simply by looking at body shape and size. Rigid and unrealistic body ideals are associated with a host of pathogenic eating and exercise behaviors that do nothing to improve one’s health,” she says.
Even in our power-to-weight based sport, lighter is not always better.
Race Weight is Not Always Healthy Weight
For some pro cyclists, their biggest battles aren’t fought against their rivals but with food. Especially for male World Tour riders, the pressure to whittle away every gram of spare fat until they’re down to 6 percent or lower by race day is as intense and relentless as a time trial up Alpe d’Huez.
The reward may be getting to the top of such storied climbs ahead of their opponents, but the price can be a compromised immune system, susceptibility to sickness, and a high risk for eating disorders and the body dysmorphia that goes with them.
According to the American Council on Exercise, “essential fat”—the amount needed for basic physiological function—is 2 to 5 percent for men and 10 to 13 percent for women, who also feel the pressure to be ultra lean.
When looking at some images of the leanest of the lean riders, Dr. Conor McGrane, a general practitioner who has worked as a doctor with Cycling Ireland and is a cyclist himself is alarmed.
“Body fat that low puts you at a much higher risk for osteoporosis, low hormone levels, and impaired immunity,” McGrane says. “Although female athletes are typically thought to have higher levels of eating disorders, it seems to be getting more common in men,”
A 2007 study published in the Journal of the American Dietetic Association found about 20 percent of male cyclists showed signs of disordered eating, and about half of respondents thought eating disorders were somewhat common in the sport.
McGrane believes those numbers are probably the same or higher today.
“The days of relatively burly muscular athletes has long gone, and thin, emaciated ones seem the norm,” McGrane says. “That’s a very worrying picture.”
It’s increasingly important for professional, competitive, and recreational cyclists alike to think of food as a way to fuel and support their training.
Bottom line: Health and fitness is not a one-size-fits-all concept. Weight is one part of the whole picture. Don’t assume that if you’re lean, you’re healthy, or that if you’re overweight, you’re in trouble. Build a relationship with a doctor to help you be your healthiest self and ideal weight. Oh, and move lots and enjoy the ride.