The INSIDER Summary:
- A recent study found that regardless of what you're eating, it's easier to gain weight now than it was 20 to 30 years ago.
- Americans are anywhere from 5% to 10% heavier today than they were in the '70s and '80s, the study showed.
- The study's author believes this may be because Americans are using more prescription drugs.
- They also believe it could be due to a rise in meat and artificial sweetener consumption.
- Chemicals that can cause weight gain are present in a lot of our foods.
It's easy to assume that your weight is a direct correlation of what you eat and how much you exercise.
And while that's true in some respects, those aren't the only factors that affect your weight.
According to a study published in the Obesity Research and Clinical Practice Journal, the decade you're living in can also play a role in your body weight.
The study looked at two main sets of data: the physical activity of 14,419 Americans from 1988 to 2006, and the diets of 36,400 Americans from 1971 to 2008. They then sorted that data to compare each study participant's food intake and level of activity with their age and body mass index (BMI).
The data revealed that two people of the same age exercising the same amount and taking in the same number of calories and macronutrients, but doing so in two different years — 1988 and 2006 — would have two different BMIs. More specifically, the person in 1988 would have a BMI that was around 2.3 points lower than the person in 2006.
In broader terms, Americans are anywhere from 5% to 10% heavier today than they were 20 or 30 years ago, regardless of how much they're eating and exercising.
"Our study results suggest that if you are 40 years old now, you'd have to eat even less and exercise more than if you were a 40 year old in 1971, to prevent gaining weight,"professor Jennifer Kuk, one of the study's authors, said in a statement.
Why is this the case? Kuk gave three possible reasons:
1. Americans are using more prescription drugs today.
Prozac first became available in 1988, and the use of antidepressants in the US has been on the rise ever since. Weight gain can be a side effect people experience when taking Prozac and other SSRI (selective serotonin reuptake inhibitor) drugs.
According to WebMD, up to 25% of those who take these drugs experience a weight gain of at least 10 pounds.
2. American's microbiomes have changed in the past 20 to 30 years.
The human microbiome is best described as the microorganisms that make up the body. Part of the microbiome are gut bacteria, and certain kinds of gut bacteria can make a person more susceptible to weight gain and obesity.
A common food that has a tendency to alter gut bacteria is meat, thanks to the hormones and antibiotics present in most animal products we consume. According to a study conducted by Rabobank, a Dutch bank with a focus on the agricultural industry, 2015 saw a 5% increase in meat consumption per capita in America, the largest increase since the 1970s.
In other words, Americans are eating more meat, which Kuk believes could be contributing to a change in the human microbiome and leading to weight gain for some people. According to Kuk, the rise of artificial sweeteners might also be to blame for this change in gut bacteria.
3. Chemicals that can cause weight gain are present in a lot of our food.
Everything from flame retardants to pesticides to chemicals in food packaging has the ability to alter our hormones. According to Kuk, hormones, in turn, partially control how our bodies gain and maintain weight. The more chemicals we ingest, the easier it can be to put on excess weight.
All of this is to say that you should cut yourself some slack, because when it comes to staying slender, millennials may not have the edge over their baby boomer counterparts.
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