Can a three-meal diet improve glucose control better than a six-meal diet for patients with T2D?

This study investigated whether 3 meals a day improved blood glucose control and weight loss compared to 6 meals a day for patients with Type 2 diabetes (T2D). This study found that fewer meals a day improved blood glucose control and weight loss and reduced hunger and cravings.

Controlling blood sugar levels is a central part of managing diabetes. However, using insulin to control blood sugar can cause weight gain. It is often recommended that patients with diabetes eat frequent small meals, including a snack before bed. This is believed to regulate blood sugar and allow for weight loss.

However, whether eating frequent small meals is effective remains controversial. Recent studies suggest that meal timing influences the body's sleep/wake cycle, which influences weight. Whether eating three meals per day rather than six is better for blood glucose control and weight loss in patients with T2D is under investigation.

This study had 28 patients with T2D. 14 patients were placed on a three-meal diet (3M), which included a heavy breakfast and lunch, a light dinner, and not eating after 8 PM. 14 patients were placed on a six-meal diet (6M), which included three meals and three snacks spaced throughout the day. Both groups were on their diets for 12 weeks.

After 2 weeks, patients in the 3M group lost significantly more weight compared to patients in the 6M group (1.5 kg vs. 0.3 kg). After 12 weeks, patients in the 3M group lost an average of 5.4 kg, while patients in the 6M group gained 0.3 kg. After 12 weeks, 85.7% (12 patients) in the 3M group lost at least 2 kg compared to 14.3% (2 patients) in the 6M group.

After 12 weeks, HbA1c (average blood glucose over 3 months) dropped by 1.2% in the 3M group (from 65.6 to 53 mmol/mol). Fasting glucose levels (levels of glucose in the blood before eating) were significantly lower in the 3M group than the 6M group (33% vs. 14%).

Patients in the 3M group had significantly less hunger and fewer cravings for sweets compared to the 6M diet. Patients in the 3M group also had more regular daily rhythms of genes involved in body cycles, such as sleeping, waking, and hunger.

This study concluded that patients with T2D who ate three meals a day had better weight loss, lower blood glucose levels, and fewer cravings compared to patients who ate six meals a day.

All study participants benefited from visiting with a dietician every two weeks, which makes maintaining a diet easier.

Talk to your doctor or nutritionist about eating a hearty breakfast, eating fewer meals, and not eating in the evening as part of managing your diabetes.