What's the best diet to keep the extra pounds away? According to the largest diet study to date -- this will make low-carb proponents gloat and say "Aha, I knew it!" -- it's more protein and less refined carbohydrates.

Researchers at the University of Copenhagen found that among subjects who had lost weight, those who spent the next six months following a maintenance diet high in protein and low in refined carbs were the least likely to regain any weight, and were also the least likely to drop out of the study.

Based on the findings, the researchers recommend consuming a diet of mostly protein and what's known as low-glycemic index carbohydrates, such as wholegrains. (The glycemic index or GI is a measure of the ability of carbohydrates to increase blood glucose levels, and low-GI foods cause blood glucose levels to spike more slowly.)

So what makes the high-protein, low-GI diet work? More protein and less refined carbs result in slow digestion and thus more balanced blood sugar regulation, explains Dr. Thomas Meinert Larsen, co-author of the study. Proteins are also significantly more filling than both carbohydrates and fat, and give a stronger satiating effect.

Protein-rich diet

Include in your diet high-protein foods such as lean meat, poultry, fish, eggs and low-dat dairy products, Larsen advises. Legumes are also great protein sources, as are nuts and almonds.

Low-glycemic diet

The goal is to eat as many coarse and wholegrain foods as possible (i.e. wholegrain breads and pasta, whole oats and wholegrain cereals) and limit your consumption of refined carbs, according to Larsen:

• Eat more vegetables, except corn.
• Eat bananas, grapes, kiwi, pineapple and melon in limited amounts.
• Potatoes should be cooked as little as possible. Avoid mashed and baked potatoes.
• Pasta should be cooked al dente and is best eaten cold.
• Choose rice varieties such as brown rice, parboiled rice or basmati.
• Avoid white bread, white rice and sugary breakfast cereals.
• Cut back on your sugar intake

Example of a day's menu

So what is a typical high-protein, low-GI diet like? Here's what the researchers suggest:

• Breakfast of low-fat yogurt with muesli (no sugar added), wholegrain crispbread with low-fat cheese, an orange
• Morning snack of vegetable sticks and low-fat cheese sticks
• Lunch of wholegrain rye bread with lean meat or chicken cold cuts, mackerel in tomato sauce and vegetables
• Afternoon snack of wholegrain rye bread with low-fat liver pâté and cucumber
• Dinner of stir-fried turkey with vegetables and wholegrain pasta, avocado salad with feta cheese and sugar peas