Stopping Meals 3 Hours Before Bed May Improve Blood Pressure And Blood Sugar, Says New Study

High blood pressure and high blood sugar have become extremely common. The World Health Organization (WHO) says that nearly 1.4 billion adults aged 30-79 years worldwide had hypertension in 2024. It also said that 830 million people were living with diabetes in 2022. It is important to keep both these conditions in check and take necessary steps to manage them. A new study says that stopping eating at least three hours before bed can help improve blood pressure and blood sugar levels. The study was conducted by researchers at Northwestern University and published in the journal Arteriosclerosis, Thrombosis, and Vascular Biology.

Your body follows a circadian rhythm, an internal clock that regulates sleep, metabolism, heart function, and hormone release. Eating late disrupts this by keeping digestion active when the body should rest and repair, increasing blood pressure and poor blood sugar control. Researchers asked participants to stop eating three hours before bed, dim lights, and extend overnight fasting to 13-16 hours. The study found that this simple adjustment in your meal timing, without calorie cuts, can help improve your heart and metabolic health, especially in middle-aged and older adults.

Dr. Daniela Grimaldi, research associate professor of neurology in the division of sleep medicine at Northwestern University Feinberg School of Medicine, and first author said, "Timing our fasting window to work with the body's natural wake-sleep rhythms can improve the coordination between the heart, metabolism and sleep, all of which work together to protect cardiovascular health."

Study Overview

The study involved 39 overweight or obese adults aged 36-75 who had a risk of cardiometabolic issues like diabetes and heart disease. These participants were divided into two groups, one that fasted for 13 to 16 hours overnight and other that fasted for 11 to 13 hours. Both of these groups stopped eating and dimmed the lights three hours before bedtime.

Dr. Phyllis Zee, director of the Center for Circadian and Sleep Medicine and chief of sleep medicine in the department of neurology at Feinberg and corresponding author said, "It's not only how much and what you eat, but also when you eat relative to sleep that is important for the physiological benefits of time-restricted eating."

Study Findings

Nighttime blood pressure dropped 3.5% in the intervention group. On the other hand, heart rate decreased 5% at night, with stronger daily rhythms; higher during activity, lower at rest. This reduces strain on the heart, lowering risks for conditions like hypertension. Blood sugar improved as well, with better glucose tolerance and insulin sensitivity. After glucose tests, participants' pancreases released insulin more effectively, stabilising daytime levels. Lower nighttime cortisol also helped in metabolic balance.

The authors said, "Extending overnight fasting duration by 3 hours in alignment with sleep improved cardiometabolic health in middle-aged/older adults by strengthening coordination between circadian- and sleep-regulated autonomic and metabolic activity. This sleep-aligned time-restricted eating approach represents a novel, accessible lifestyle intervention with promising potential for improving cardiometabolic function."

Potential Limitations

The study was small as it included only 39 participants and was conducted for a short-term (7.5 weeks). It also included mostly women. Hence, larger trials are required. Also, this eating pattern might not be ideal for everyone, such as shift workers or those with eating disorders.

Ways To Implement The 3-Hour Rule

• Plan Your Last Meal: Aim for dinner by 7 PM if bedtime is 10 PM and adjust based on your schedule. Choose lighter, balanced evening meals with protein, veggies, and healthy fats like dal, paneer sabzi, or grilled chicken with salad.
• Plan A Wind-Down Routine: Three hours before bed, dim lights and avoid screens. Use warm yellow bulbs or night mode on phones which signals your body it's rest time. Sip herbal tea (chamomile or tulsi) or warm water instead of eating.
• Manage Challenges and Stay Consistent: During weekends, stick to the same bedtime rhythm, even if you're sleeping in. During social outings, opt for early dinners or pack light snacks like nuts if needed.

Disclaimer: This content including advice provides generic information only. It is in no way a substitute for a qualified medical opinion. Always consult a specialist or your own doctor for more information. NDTV does not claim responsibility for this information.