High fasting blood sugar in young adults: Why you need that 20-minute walk after dinner

 

Written by Dr V Mohan

Source: https://indianexpress.com/article/health-wellness

One of my patients was worried about the high fasting glucose levels in his 22-year-old son. He was worried if the dawn phenomenon, when hormones in the body naturally makes every morning and elevates blood sugar, could be worrisome for non-diabetic people like his son, too. Is it indicative of diabetes in the future?

Yes, the dawn phenomenon can affect both individuals with and without diabetes. The human body experiences the lowest level of blood sugar at 3 am. Then the body releases hormones like cortisol, growth hormones and adrenaline to prepare us to wake up, usually between 3 am and 10 am. They signal the liver to boost the production of glucose, which provides energy that helps you wake up. In non-diabetic individuals, insulin works efficiently and brings the blood sugar back to normal. But in people with diabetes — or those with insulin resistance — the body cannot counteract this hormone-driven rise effectively, leading to high fasting blood sugar levels.

Does a slightly high fasting sugar mean a non-diabetic person will get diabetes?

Not necessarily. For non-diabetic individuals, it can be an early warning sign rather than a diagnosis. It tells us that lifestyle changes are needed now to prevent diabetes later. The occasional morning high will have little impact on your HbA1C, average blood glucose count over three months, which is an indication of whether your blood sugar management is effective enough. But if those highs become consistent, they could push up these levels too.

What is the best way to manage the dawn phenomenon for both groups?

The most effective and safest strategy is lifestyle management, especially physical activity. A simple 20–30-minute walk after dinner is one of the best activities to combat the dawn phenomenon in both diabetic and non-diabetic individuals. It helps muscles use glucose, improves insulin sensitivity and reduces the overnight rise in sugar levels.

Is walking really enough, even for people with diabetes?

Yes. Walking is sustainable and highly effective. Consistency matters more than intensity. Even light activity after dinner makes a meaningful difference.

What about morning exercise?

Morning exercise is good for overall health but when focusing on the dawn phenomenon, intense early morning workouts can sometimes increase blood sugar temporarily due to stress hormones. Gentle activities like yoga, stretching, or a calm walk are better choices in the morning. A Chinese study showed that moderate-intensity aerobic exercise before breakfast reduced the morning rise of blood glucose in diabetes patients. It significantly reduced blood glucose fluctuations and improved blood glucose control throughout the day.

I usually eat dinner late and go straight to bed. Could that worsen the problem?

Late dinners followed by immediate sleep reduce glucose utilisation overnight for both diabetic and non-diabetic individuals. Ideally, dinner should be light and finished at least two to three hours before bedtime, followed by light movement.

What to do if lifestyle changes don’t work for people with diabetes?

If fasting sugars remain high despite walking, timely meals and good sleep in people with diabetes, we may need to adjust night-time treatment. This can include increasing the dose of long-acting insulin at night or modifying night-time oral hypoglycaemic agents (OHAs). These changes help control the early morning hormone-related sugar rise.

Should patients adjust insulin or tablets on their own?

They can make adjustments with the guidance of their healthcare professional. This helps ensure changes are safe, effective and based on fasting blood sugar trends and the risk of low blood sugar.

Can technology help understand this better?

Continuous Glucose Monitoring (CGM) tracks glucose levels day and night, clearly showing when sugar starts rising. It helps us confirm the dawn phenomenon, adjust insulin or medication safely, and also shows how effective walking and meal timings are.

Is CGM useful as a predictive tool for non-diabetic people?

CGM helps non-diabetic individuals identify hidden sugar spikes related to late meals, poor sleep or stress, long before diabetes develops.

Whether someone has diabetes or not, managing the dawn phenomenon requires timely meals, regular post-dinner activity, good sleep and stress control. For people with diabetes, medication adjustment and CGM add precision. Small daily habits make a big difference to long-term blood sugar health.