How one glass of water helps you lose weight while still feeling full

We can do all the best exercises for weight loss, crunches and tabata circuits around, but that age-old adage holds true: abs are made in the kitchen. If you're looking to lose weight on your stomach (or anywhere else, for that matter) you need to be mindful of portion control.

Eating smaller portions at mealtimes isn't just about having a slimmer waist: it can also help you live longer. People living in the "blue zones" – areas of the world like the Japanese island of Okinawa, whose occupants tend to live long and stay healthy in their old age – eat until they're 80% full. 

Outside of the Blue Zones, we often tend to overload our plates as we're used to stuffing ourselves until we're too full, but we can get around this by drinking a large glass of water before mealtimes. 

A study published in the journal Clinical Nutrition Research recruited 15 participants (eight women and seven men) with average ages of 26.4 for women and 23.5 years for men. The study had them drink a glass of water before mealtimes and studied whether it lowered energy intake and satiety levels.

The results were extremely positive. The study found "pre-meal water consumption led to a significant reduction in meal energy intake", reducing the amount of food the participants ate. 

However, the participants recorded no significant drop in their satiety levels, so they still felt as full as they ever did.

Although the actual mechanism causing this is unknown, the researchers concluded pre-meal water consumption could be an effective weight control strategy.

Water consumption isn't just helping to reduce your appetite: it's also an extremely effective weight loss drink in its own right. It's a ready-made, calorie-free alternative to sugary sweetened beverages, and the human body needs it to survive. 

Drinking water helps retain cognitive function, allowing your brain perform at maximum capacity, and it also helps relieve constipation. Everything from your energy levels to the function of your internal organs also take a nosedive when you're dehydrated. 

That's enough to get anyone reaching for the best water bottle for the gym. Not all bottles are made equal: some cheaper ones leech plastic and BPA into their liquids over time. Keep one of these bottles handy by your desk to stay hydrated throughout the day.