22/01/2019 11:49 GMT | Updated 22/01/2019 11:49 GMT

Women Live Longer If They Stay Close To Their Weight Aged 20, Study Says

The study encourages people to stop yo-yo dieting.

If you want to see your 90th birthday, scientists are recommending you try and stay within a stone and a half of the weight you were aged 20. That’s if you’re a woman.

Maintaining your weight might sound like the impossible (we envy our teenage metabolism, too) – as most adults gain on average 1lb (or half a kilogram) every year they age. But a new study has found that, as a woman, if you’re able to reduce this incremental rise, you’re going to have better odds of living longer. 

The study found women whose body mass index (BMI) had increased by more than eight points since age 20 were 19% less likely to reach 90 than those whose BMI had changed by less than four points. 

The men in your life won’t face the same pressure as the study found no link between body size and longevity for men.

Nor does it mean if you were overweight at 20 you should remain, or return to, being overweight – it’s encouraging people to avoid huge fluctuations in their weight throughout their lifetime. 

[Read More: How to take your very first steps into fitness, from walking to running]

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The study, published in the Journal of Epidemiology and Community Health, looked at 7,807 women between the ages of 68 and 70 and found those who had restricted their weight gain over the decades were 32% more likely to reach age 90 than those registering as “obese”.

Researchers found that dieting wasn’t the only way to achieve this. It concluded that for women, there’s a sweet spot of around 60 minutes of physical activity per day – which can include walking, cycling, gardening and playing sport – to keep peak physical fitness.

And while it found no link between BMI and longevity in men, it did find men who were physically active for an hour and a half a day at retirement had the best chance of reaching 90.

The research team are keen to stress that, as an observational study, they can’t establish explicit cause and effect – but lead author Lloyd Brandts says there’s “no harm” in middle-aged people adjusting their lifestyle accordingly.