If you are medically overweight, like 39% of the world’s population, you might be asking yourself, “what causes weight gain?”

You may be here because you’re trying to lose weight. More than half of Americans are currently attempting to lose weight on any given day of the year. (1)

Ask most doctors what causes weight gain or the inability to lose weight and you’ll likely hear that the number of calories you consume exceeds the number you burn. Not as commonly, you may hear about other possible causes such as too much of the stress hormone cortisol.

Though conventional medical advice often associates weight gain with overeating, lack of physical activity, too much snacking, and other “mistakes” on your part. You may even experience bias from your physician. (Do a search for “are doctors biased against overweight and obese patients” to see for yourself.)

One of the primary reasons for weight gain is diet culture.

"You Must Be Doing Something Wrong"

Recently, I went to an orthopedic doctor because I’d been having some pain in my left foot. We met for the first time after an x-ray. She made her diagnosis within the first 3-5 minutes of being in the room. The conclusion was that I had a simple case of nerve entrapment.

The doctor wanted to give me a steroid shot, but I declined and explained that I just wanted to know what was causing the pain. With this information, I could start working on whatever was going on.

In addition, expressed concern that my gradual weight gain since my early forties might be a contributing factor to my foot pain.

This brings me to the topic of this post.

At the end of a visit that lasted all of 7 minutes tops most of which we spent talking about my foot, she had sized me up.

The tall, thin, elderly female doctor explained that my weight gain wasn’t normal. She further elaborated that there had to be something I was “doing wrong” if I’d been steadily gaining weight. Either I was eating too much, not the right thing, or more than the energy I was using up.

Is it really that simple? No.

Overweight and obesity are complex issues and are rarely as simple and straightforward as this particular doctor suggests. Just because you're overweight doesn't mean you're doing something wrong.

What causes weight gain?

Some studies indicate that overweight and obesity may have plenty to do with our genetics. Gene variants studied show women with certain alleles have more fat mass and a lowered ability to burn it off.

Genetics and Body Weight

Conflicting studies from around the world make it hard to say for sure if there is a correlation between single nucleotide polymorphisms (SNPs) and obesity. Your body may do better on certain types of diets due to your genes. You can find out using SelfDecode.

Though we do know that hormones play a major role in weight issues. Leptin and Ghrelin are worth studying if you struggle to lose weight. Read “it’s not your fault you are overweight.”

You may notice you gain weight like your parents or grandparents, as I do.

My maternal grandmother, who I have no doubt had undiagnosed blood sugar issues, gained weight in her arms and around the middle. (She didn’t like to go to the doctor, but had all the symptoms of blood sugar imbalances.)

Like my grandma, the weight I gain tends to accumulate in my arms as well. Unlike my grandmother, I have enviable A1C results. (A1C is a simple blood test that measures your average blood sugar levels over the past 3 months. It is a more accurate measurement of true blood sugar levels than daily glucose testing, which I also do 2-3 times per month.)

Another reason for frustration with the orthopedic doctor’s suggestion; she doesn’t know anything else about my health. Her assessment was based on my foot x-ray and my appearance. I’m overweight.

Does Metabolism Slow As We Age?

A new study implies previously accepted theory on weight gain with age may be incorrect.