fat person wearing tight shirt
Brittany Hambleton
Brittany Hambleton
January 20, 2024 ·  6 min read

6 Reasons We’re Fatter Than 30 Years Ago, It’s Not Only Food Or Exercise…

Most of the world has prescribed to the “calories in, calories out” model for weight loss. In other words, if you want to lose weight, you simply need to consume fewer calories (ie eat less) and expend more calories (ie exercise more). If the science of weight loss is so simple, then, many experts are asking why we’re fatter than we used to be?

As a whole, we humans have gotten heavier over the last few generations. It turns out, however, that the reasons behind this are a lot more complicated than we’re simply eating too much and moving too little. Now, don’t get us wrong, a caloric deficit is fundamental for weight loss, but there are other aspects that can be contributing to obesity.

A team of researchers at Toronto’s York University determined that today’s generation will have a harder time managing their weight than their parents and grandparents did. 

Read: How to get rid of side boob fat

Why We’re Fatter: The Generational Divide

The researches at York University analysed dietary data from more than 36 thousand American adults from the National Health and Nutrition Survey between 1971 and 2008. They also looked at the physical activity frequency data of over 14 thousand adults from 1988 to 2006 [1].

They found that earlier generations had an easier time managing their weight than today’s millennials and gen Y. In other words, earlier generations could, in general, eat more and exercise less, and it would have less of an impact on their body weight.

“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,” says Professor Jennifer Kuk in the School of Kinesiology and Health Science. “However, it also indicates there may be other specific changes contributing to the rise in obesity beyond just diet and exercise.” [2]

Calories In vs Calories Out? It’s Not The Easy…

More specifically, they found that people who reported eating the same amount in 2008 as someone from 1971 was about ten percent heavier than the older individual at the same age. People in 2006 with the same activity level as someone from 1988 were found to be about five percent heavier.

For this reason, the researchers concluded that over the long term, the “calories in, calories out” method of weight loss may not be the only thing to consider.

“This is because weight management is actually much more complex than just ‘energy in’ versus ‘energy out’,” says Kuk. “That’s similar to saying your investment account balance is simply your deposits subtracting your withdrawals and not accounting for all the other things that affect your balance like stock market fluctuations, bank fees or currency exchange rates.” [2]

Read: High-fructose and high-fat diet damages liver mitochondria, study finds

6 Reasons Why We’re Fatter Than We Used to Be

Kuk says that many factors can impact our body weight, including our environment and our lifestyle. Ultimately, she says that maintaining a healthy body weight today is more challenging than ever. 

The following list is just six of the reasons why we’re fatter than we were fifty years ago.

1. Prescription Drugs

Several studies have come to the conclusion that the overuse of pharmaceutical prescription drugs is contributing to today’s obesity problem. Weight gain is a common side effect for many of these drugs, including diabetes medication, antidepressants, and antipsychotics [1]. 

These drugs can contribute to weight gain in a variety of ways. They could increase your appetite, slow your metabolism down, or even change your body’s fat-burning capacity [3].

2. Chemical Exposure

The York researchers also noted that chemicals in everyday products may also be contributing to higher obesity rates. In addition, agricultural beef cattle receive exogenous sex steroids to help them gain weight faster and to increase feeding efficiency. The researchers said that it is possible that these steroids are affecting human health [1].

According to the FDA, 80 percent of all the antibiotics we use in the United States go toward animal agriculture. Research suggests that eating this antibiotic in meat may make humans gain weight in the same way that it does animals [4].

The various chemicals that we can be exposed to including heavy metals, some solvents, pesticides, BPA, organophosphates, phthalates, PCB, and PBBs may be contributing to weight gain [5]. This is particularly true for children, who are still in the developmental stages of life. Exposure to these chemicals at such a young age causes them to form more fat storage cells than they otherwise would [5].

3. An Altered Gut Environment

Your digestive system contains millions of bacteria. Collectively, they make up your gut microbiota. Studies have shown that obese people have different gut bacteria than those who are a healthy weight [6]. 

Scientists still don’t fully know how your gut microbiome and obesity are related. Some experts believe that it may be because the gut bacteria of those with excess weight are more efficient at getting energy from food. In turn, this would ultimately increase the total caloric value of their diet [7].

Read: 16 Fish You Should Consider Never Eating

4. Genetics

Children who have parents or grandparents who are obese have a much greater risk for obesity compared to their peers who have normal-weight parents. This is because the genes you inherit from your parents may determine your susceptibility to gaining weight [8].

While we cannot blame genetics alone for causing obesity, they do predispose someone to weight gain.

5. Junk Food Advertising

Messages surrounding what we should and shouldn’t eat bombard us every day. Unfortunately, a large portion of this information does not teach children and adults how to eat healthy, and much of it points you in the direction of junk food.

Exposing children to TV ads for unhealthy food products puts them at a much greater risk for obesity. Some research has shown that children who watch more than three hours of television per day are fifty percent more likely to become obese. Perhaps not surprisingly, food ads make up fifty percent of all the ad time on children’s shows [9].

Conversely, children who learn about a healthy diet are less likely to have weight problems as adults [10].

6. The Environment

For many people, healthy food is simply not as available as unhealthy food. Many urban neighbourhoods or rural towns have what are known as “food deserts”, which is when there is a lack of access to healthy, affordable food.

People living in these areas also typically have a lower income, and may not have a vehicle to drive the further distances required to buy groceries. These people are more likely to be obese because they cannot access healthy food options [11].

What Can You Do About It?

Of course, if you want to avoid excess weight gain, you do still have to moderate your energy input and output. This means being careful not to overeat, and exercising regularly.

That said, what you eat is as important (if not more important) than how much you eat. To lower your risk for obesity, try as much as possible to avoid foods that contain preservatives, hormones, or pesticides. If you can, buy whole foods whenever possible, and cook from scratch as opposed to buying pre-packaged, processed foods [12].

If you are struggling with your weight, consider talking to your doctor or a dietician. They can help you determine what may be causing you to gain weight, and come up with an action plan to help you regain control of your health.

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