You can eat well and exercise regularly and still harm your heart if sleep is neglected. During good-quality sleep, blood pressure naturally dips by about 10 to 20 per cent, giving blood vessels a rest. Poor or fragmented sleep interferes with this dip, keeping heart rate and stress hormones higher than they should be. Over time, it also fuels low-grade inflammation, damages the lining of blood vessels and speeds up the build-up of fatty plaque in the arteries. Sleep loss reduces insulin sensitivity, raising the risk of type 2 diabetes, and disrupts appetite hormones, leading to cravings and weight gain. Irregular sleep timing matters as much as duration, and weekend lie-ins cannot fully undo weekday sleep loss. Diet and exercise protect the heart, but they cannot fully offset the effects of chronically poor sleep.
