According to researchers from the Czech Republic, eating a big breakfast and a large lunch is better if you're trying to control weight and blood sugar levels than six small meals a day.
The study, published in the journal Diabetologia, found that frequent eating of high-fat and high-sugar foods increased cholesterol stores in the liver and fat around the waist – but eating larger portions less frequently did not.
Participants were asked to follow one of two diets which both had the same macronutrient and calorie content but each contained 500 calories less than the recommended daily amount.
One group of 27 ate six small meals for 12 weeks, while the second had a large meal at breakfast and lunchtime. The groups then switched regimens and continued for a further three months.
The experts took measurements of insulin sensitivity, liver fat content and the function of pancreatic beta cells – which produce insulin.
Body weight fell in both diets – but there was a greater loss for those eating bigger meals twice a day.
Those eating twice a day lost around half a stone (3.7kg), compared with just over a quarter of a stone (2.3kg) for the snackers.
Liver fat content also reduced for both groups, but by a slightly larger amount for those on two large daily meals.
The study also showed more beneficial levels of chemicals such as the hormone glucagon and C-peptide, a protein involved in insulin synthesis, among people eating two meals a day- which would benefit diabetics.
Dr Hana Kahleová, of the Institute for Clinical and Experimental Medicine in Prague, said: "These results suggest that, for type 2 diabetic patients on a calorie-restricted diet, eating larger breakfasts and lunches may be more beneficial than six smaller meals during the day.
"Further larger scale, long-term studies are essential before offering recommendations in terms of meal frequency."