It is not controversial to say that an unhealthy diet causes bad health.

毋庸置疑，饮食不健康对身体不好。

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The detrimental effects of an unhealthy diet and insufficient exercise are not limited to your body.

不健康的饮食和不充分的锻炼带来的有害影响并不局限于你的身体。

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An unhealthy diet will nullify the effects of training.

不健康的饮食会抵消锻炼的效果。

《牛津词典》

But he pointed out that statins would not affect all the negative effects of an unhealthy diet.

BBC: 'Give out statins with junk food'

The prevalence of diseases related to an unhealthy diet and lifestyle is also on the rise, the government said.

FORBES: Fat In China

Those who watch huge amounts of TV are also probably more likely to have an unhealthy diet and be overweight.

BBC: Can watching TV make you die younger?