Why it was EASIER to be thin in the 1980s

Do your parents lecture you about how thin they were at your age?

Well, they may have had an unfair advantage, after a recent study revealed people were 10 per cent heavier in 2008 than in 1971, despite eating the same calories. 

And they were around 5 per cent heavier in 2006 compared with 1988, despite doing the same amount of exercise.

Now, the authors of the study have explained they believe there are factors beyond calorie intake and exercise that are causing today's millenials to gain more weight.

Professor Jennifer Kuk, from York University, Toronto, told the Atlantic that increased exposure to chemicals and pesticides; anti-depressant use and a change in our gut bacteria are three key reasons why people today might be fatter despite similar diets.

Pesticides and chemicals in food packaging may be altering our hormones, which affects the way our bodies gain weight.

Antidepressant use has also soared since the 1970s, she said.

For up to a quarter of people, antidepressants including the selective serotonin reuptake inhibitor (SSRI) drugs, 'blockbuster' pills in the US, cause weight gain.

In the US, antidepressants are the third most commonly prescribed drug. 

In the UK, the number of antidepressant prescriptions has increased more than twofold between 1975 to 1998, according to the Journal of Public Health.

In 1998,  a total of 23.4 million antidepressant prescriptions were issued by UK GPs.

Finally, Professor Kuk told Atlantic journalists that people’s ‘microbiomes’, their gut bacteria, may have changed in the last 35 years.

More meat and animal products contain hormones and antibiotics that promote growth.

Over time, constant exposure to these may change a person’s microbiome and cause them to pile on the pounds more easily.

Artificial sweeteners used to flavour food may also play a role, as it may cause insulin resistance.

Insulin is the hormone that breaks down sugar into energy, and if the body becomes resistant to it, excess glucose circulates in the bloodstream.

The excess sugar remains in the bloodstream, which is sent to the liver, where it is converted into fat.

In the study, she said other affect our body weight, including genetics, timing of food intake, stress, and even night-time light exposure.

'There's a huge weight bias against people with obesity,' Professor Kuk told the Atlantic. 

'They're judged as lazy and self-indulgent. That's really not the case. If our research is correct, you need to eat even less and exercise even more just to be same weight as your parents were at your age.'

Weight management is actually 'much more complex than just "energy in" versus "energy out", she concluded, in a statement on the study, published in the journal Obesity Research & Clinical Practice.

'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.' 

 'Ultimately, maintaining a healthy body weight is now more challenging than ever,' she said.

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