One more reason to cook at home: a new study has found that eating out even once a week may lead to higher blood pressure.

According to Science Daily, researchers from Duke-NUS Graduate Medical School Singapore compared health data like blood pressure and body mass index with lifestyle factors like physical activity level and the number of meals eaten out. They collected data from 501 university students, aged 18 to 40, to determine an association with hypertension, AKA high blood pressure.

About 27% had “pre-hypertension,” or slightly elevated blood pressure, which the study linked to eating out. Even one extra meal out raised the odds of pre-hypertension by 6%. Overall, 38% ate more than 12 meals out per week.

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The gender breakdown for pre-hypertension was far more prevalent in men (49%) than in women (9%). Across genders, those with pre-hypertension were more likely to engage in unhealthy lifestyle choices that causes hypertension in the first place: eating out, low physical activity levels, and smoking.

The lead researcher on the study said it’s important that lifestyle factors are taken into account when studying hypertension. Her research is a reminder to be aware of salt and calorie content when dining out — and that if you really want to know what’s in your food, you have to cook at home.

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