Why Being a Little Overweight May Be OK (2024)

You can easily calculate your score using a BMI calculator.

BMI and Your Health

Virtually all studies using BMI scores agree on a couple of points:

• People with obesity or extreme obesity have a greatly increased risk of all-cause mortality.
• People who are underweight also have an increased risk of death. This is thought to be mainly because of underlying disease processes—such as heart disease, lung disease, cancer, or infection—which, on their own, often produce weight loss with disease progression.

If there is a controversy, it centers around individuals with overweight status, but not obesity. This includes those with BMI scores a little over 25. Most studies have shown increased medical risk even with this mild state of being overweight, but a few studies show a slightly lower risk for these individuals.

Several explanations for this apparent discrepancy have been suggested. The one that has the most traction is the idea that BMI is not a good measurement for people who are extremely fit.

The Obesity Paradox

Since the early 2000s, research into mortality for people with heart disease has found that survival statistics favored those who were in the overweight BMI range. Further large systematic reviews and meta-analyses of studies have supported this finding.

The idea that people whose BMI measures are above the normal range may have reduced cardiovascular mortality has been called the obesity paradox.

What the Research Says

A 2015 study published in the journal Heart compiled data from 89 studies, including more than 1.3 million people who had coronary artery disease. Those who were underweight had the highest risk of both short-term and long-term mortality (over three years).

People with overweight status or obesity had a lower risk of short-term and long-term mortality compared with those who had a BMI in the normal-weight range. However, people with obesity had a higher risk of mortality after five years of follow-up.

A 2018 study analyzed 65 prior studies involving 865,774 people who had coronary artery bypass graft surgery or coronary revascularization with percutaneous coronary intervention.

The study confirmed that compared to normal-weight individuals, all-cause mortality was increased for underweight people and lower for those with overweight status, obesity, or severe obesity. Being in the overweight BMI category was associated with the lowest risk of major adverse cardiovascular events.

How Well Does BMI Measure Risk?

Why does the obesity paradox exist? Current thinking is that BMI is an insufficient measure of a person’s cardiovascular risk since it fails to take into account a person’s muscle mass and overall cardiorespiratory fitness.

On the other hand, people who may formerly have been overweight and go on to develop heart disease often develop muscle wasting, and their BMIs may drop back into the normal range.

Because of this, BMI by itself may give a misleading picture of a person’s cardiovascular health.

Factors That Determine if Your BMI Is Healthy

Some of the variables that can determine whether an elevated BMI is still healthy for you to include:

• Fitness level: If you follow a regular exercise routine and you have good muscle mass, you may have a higher BMI. A high BMI in very fit people is not associated with greater health risks.
• Age: A younger adult may have less body fat than an older adult with the same BMI.
• Sex: Females tend to have more body fat than males, even when they have the same BMI.
• Ethnicity: People of different ethnicities have variations in frame size, fat distribution, and so on, which affects what is considered a "normal" BMI for each group.

The range of healthy to unhealthy BMI may not be accurate for everyone. This is why many experts now say that, instead of relying onBMI to determine whether weight is contributing to cardiovascular risk, abdominal fat should be the greater focus.

Abdominal Fat and BMI

Having too much fat—specifically, too much fat in your midsection—places significant metabolic stress on the cardiovascular system and increases the risk of cardiovascular disease.

While the BMI score is sometimes useful and easier to measure, the waist-to-hip ratio is probably the more important index of cardiovascular risk.

So, if you have a BMI of 27, for example, you are in the “overweight” category. Before drawing conclusions about this, answer this one question: Is your waist size less than your hip size?

• If yes, then the “excess” weight contributing to your BMI score is likely muscle and not fat.
• If no, you likely have centrally deposited fat, which is cause for concern.
  

How Can I Lower My BMI?

You can work to lower your BMI by changing the way you eat and staying active. Focus on plant-based foods like fruits, vegetables, and whole grains, and avoid foods that contain a lot of unhealthy fats and added sugar.

Try to get at least 30 minutes of exercise a day, five days a week. This can be as simple as a brisk walk or a bike ride.

Avoid crash diets and fad diets. These may work for short-term weight loss, but sustainable change involves making permanent changes to your activity levels and the way you eat.

Summary

A higher BMI is associated with a greater risk of health problems. But the risks are clearer for people with obesity versus those with moderately overweight status.

Research has suggested that people who are moderately overweight may have a lower overall risk of mortality and health problems. Some researchers think this is because BMI is not a good measurement for very fit people.

A better measurement of risk may be the amount of abdominal fat you have. If you have a higher BMI but your waist size is less than your hip size, you are probably at a healthy weight.