Do you watch what you eat, but still pack on the kilos? Stephanie Osfield finds nine reasons why you can't shift that weight.

1. Stress = spare tyre
Living on the run? All that stress can give you a jelly belly. Research at Yale University in the US found that women carrying abdominal fat report higher levels of stress and anxiety compared with women who store fat around their hips. "When we're stressed, our adrenal glands release a hormone called cortisol, which makes us store fat in case of famine," says David Cameron-Smith, associate professor in nutrition sciences at Deakin University, Melbourne. "This fat gain can become concentrated in our most active fat cells around the abdomen, which are highly sensitive to stress hormone receptors. Fat storage in this area is dangerous because it drains quickly to the liver, combining with cholesterol to enter your bloodstream, and increasing your risk of heart disease down the track." Try: Working out. Exercise sparks the release of brain chemicals called beta-endorphins, which improve mood and promote calm. Aim for 30 minutes on most days. Plus, block out "me time" breaks in your diary.

2. Food labels that fool you
Your choices may not be as healthy as you think if you're being misled by these claims.

• 97 per cent fat-free: Those lollies or biscuits may be low in fat, but that's only part of the picture; don't ignore the salt, kilojoules and sugar content.
  
• Lite or light: Often refers to the colour or taste of a product, so a "light" food might still be high in kilojoules and/or fat.
  
• Sumptuous images: That juicy apple or ripe red capsicum in the picture may only make up five per cent of the flavour in the food - check the ingredients.
  
• Health bars: When Choice magazine tested 150 cereal bars, only 13 were nutritionally sound while most were so loaded with fat and up to 20 per cent sugar that they were on a par with a chocolate bar or packet of chips.
  
• No added sugar: These products may be sweetened by another source, such as dextrose, fructose, glucose or maltodextrin - which still behaves like sugar in the body and spikes insulin levels. Try: Avoiding processed food altogether - fresh is usually a better option.

3. The tank is always full
For most of us, it's a stretch to recall intense hunger because we eat out of habit, not emptiness. "That's the problem with weight-loss programs, which only focus on lowering kilojoules," explains Dr Rick Kausman, author of If Not Dieting, Then What? (Allen and Unwin, $29.95). "If you eat when you are not really hungry, there's no appetite signal to tell you to stop."
Try: Measuring your hunger. According to Dr Kausman, on a 0-10 scale, if 0 = starving and 10 = stuffed, you should eat at about a 2.

4. You're drinking excessively
Before you reach for another Mudslide or Margarita, remember this - your body treats alcohol like a poison so it gets rid of it quickly. "This means your body delays burning off the kilojoules from food so excess kilojoules, particularly from fatty foods, may get stored as excess weight," reveals Dr Kausman.
Try: Avoiding cocktails, which pack a stronger kilojoule and alcohol punch. And alternate each glass of wine with a tall glass of H20.

5. Being sleep deprived
Skimping on sleep can change the hormone balance that controls your appetite. "Research has shown that a short sleep can result in your body producing less leptin [which regulates appetite] in the brain and more ghrelin in the stomach, which triggers feelings of hunger and cravings for high-energy food," explains Sarah Biggs, an expert in sleep disruption at the University of Adelaide. Try: Not exercising, drinking caffeine or eating a large meal after 8pm, as this can cause alertness when you should be asleep.

6. Too much exercise
The more you sweat the hungrier you get. That's the cruel truth according to research from the University of Ottawa in Canada, which found that when women do high-intensity exercise, they eat more kilojoules in the following hour than women who do moderate exercise or none at all. Worse still, the extra kilojoule intake is high enough to negate the energy burned up by the huff 'n' puff workout. Try: Fuelling your body with a snack of wholegrain carbs and protein in the hour before exercise will give you a slow, sustained release of energy. Afterwards, fill up on water. If you're still peckish, opt for something healthy like a banana or tub of yoghurt.

7. Shoulder to the grindstone
Do you often work back or stay at your desk during lunchtime? Research at the University of Leeds in the UK found that women who work long hours eat more high-fat, high-sugar snacks, smoke more and exercise less. Try: Keeping your desk drawer stocked with quick-fix, non-perishable, healthy foods like canned tuna, baked beans, rye crispbreads, nuts, rice crackers and tahini for those cravings at work. Eat meals and snacks away from your desk so you can slowly savour each mouthful and feel more satisfied.

8. Living together
Once couples cohabitate, their weight, blood pressure and cholesterol climbs and their exercise drops off, according to research from the University of Western Australia. "Women on average gain just under two kilos," states Valerie Burke, research fellow from the university's School of Medicine and Pharmacology. "In part, this is because couples tend to cook more gourmet-style meals and women start serving themselves portions that are as large as their partner's." Try: Tandem workouts where you cycle, lap the pool, play tennis, walk, talk and watch the sunset together. That way you'll still fit in to your his 'n' hers bathrobes for years to come.

9. You need more protein
Recent research at the University of Washington School of Medicine in the US found that increasing protein, while maintaining carbohydrate intake, helps people feel fuller for longer, lose weight and decreases their levels of the hunger hormone, ghrelin. Try: Including the following in your diet: an egg or sardines at breakfast; tuna or half a cup of baked beans at lunch; and chicken or red meat at dinner. Good protein snacks include low-fat yoghurt, hummus, cottage cheese and nuts.