‘My blood sugar level rises to 180 mg/dL after a meal and tends to stay there for two hours’: What does such a spike mean?

Is a post-meal blood sugar spike something to worry about?

Not necessarily. A small, gradual rise is expected. We generally are worried about sudden jumps or very high readings. For most people with diabetes, we recommend keeping blood sugar levels below 180 mg/dL in the one to two-hour window after a meal. If your reading is below that and comes down steadily within three to four hours, that’s usually acceptable.

So if blood sugar climbs to 180 mg/dL and then slowly declines within the next hour or two, should we be worried?

This spike is not dangerous. It becomes a concern when the sugar levels go beyond 180 or 200 mg/dL very quickly and do not come down even after a long time.

So, why do such spikes occur?

The food we eat matters a lot. The foods that are digested quickly and release glucose rapidly into your blood are the main culprits. These are foods high in refined carbohydrates or added sugars. For example, white rice, white bread, sweets, pastries, sugary drinks and processed snacks. These foods can cause sudden rises.

Can avoiding carbs altogether prevent these spikes?

Carbohydrates are important for energy. What matters is the quality and portion size. Whole grains, brown rice, oats, lentils, beans, fruits and vegetables release glucose more slowly. They give you steady energy and help prevent spikes.

That sounds manageable. Are there other tips to prevent spikes?

A few things really help:

1. Pair carbs with protein or fibre – Combine rice, dal and vegetables. With proteins and fibres taking long to digest, this reduces the glycaemic index (a measure of how quickly sugar is released into the bloodstream) and blood sugars rise gradually.

2. Eat small frequent meals – Having a large portion of meals at once increases blood sugar quickly.

3. Stay active after meals – A 10 to 15-minute post-meal walk helps muscles absorb glucose better.

4. Avoid sugary drinks – They cause the fastest spikes.

To summarise, a spike is when sugar goes higher than 180 mg/dL after meals and continues to stay there for long. One can prevent these spikes by having a balanced meal, doing regular physical activity and keeping to sleep hygiene and mindful lifestyle practices. Remember, occasional variations can happen but if you notice frequent spikes above 180 mg/dL, you need to consult your dietitian and your doctor.

(Dr Mohan is Chairman, Dr Mohan’s Diabetes Specialities Centre, Chennai)