How long will you lie there you sluggard? When will you get up from your sleep? A little sleep, a little slumber…and poverty will come on you like a bandit. Proverbs 6:9-11

Most cultures have wise sayings about the negative result of being lazy or sleeping too much. But in today’s culture we seem to have the opposite problem – not enough sleep. Stress, computers, television, long work hours and burning the candle at both ends are just some of the habits that steal our sleep – and it’s making us fat.

Sleep is not optional, it’s essential to good health. While we sleep our body releases substances that fight infection, build and repair muscle, control appetite, consolidate memory (remember this if you are studying) and promote maturation in teenagers.

Lack of sleep makes our body work differently. It reduces insulin sensitivity and alters two key hormones: leptin and ghrelin. Leptin reduces hunger so it’s good to have plenty around. But lack of sleep, especially when combined with stress, drops those appetite suppressing leptin levels.

If you’ve decided to cut back on bread in an attempt to control weight, think again. Wholegrains were one of a handful of winning foods in a new study looking at long term weight control. The researchers from Harvard Medical School and Harvard School of Public Health found that people who ate more wholegrains actually gained less weight over four years.

Published in the New England Journal of Medicine this study of over 120,000 people found that people who ate more unprocessed foods, specifically wholegrains, nuts, yoghurt (reduced or full fat), fruit and vegetables gained the least weight over a four year period.

These people didn’t just keep on eating the same amount over the four years; they actually increased the number of serves of these foods they ate each day. More food means more kilojoules so why didn’t they gain weight? These foods are all high fibre (apart from yoghurt) nutrient rich foods which provide long lasting satiety. They keep blood sugars stable without the rapid spikes that experts now think contribute to weight problems. If you eat lots of these foods chances are you won’t feel quite so desperate to munch on crisps or slurp on a soft drink.

Eat less, exercise more. Weight loss is a simple equation, or is it? Recently at the Australian Institute of Food Science and Technology conference I was intrigued to hear a number of speakers mention how the type of bacteria living in our digestive system can influence our weight.

Does that mean if I eat a whole lot of probiotic yogurt I will magically lose that extra padding around my stomach? It’s not quite that simple.

Our digestive system is teeming with microorganisms. In fact our body contains more bacteria than cells. We have around 10 trillion cells but around 100 trillion bacteria. In recent years scientists have discovered just how essential they are for health including:

• stimulating the immune system
• breaking down toxins and carcinogens in food
• fighting against bad bacteria such as e.coli, salmonella and clostridia
• fermenting food to release and absorb nutrients
• regulating inflammation
• regulating energy uptake from the gut

Last night I heated some extra virgin olive oil and fried chopped potatoes, onion and asparagus. After a few moments I tossed in some spinach leaves and chopped tomato, then poured over beaten eggs. A sprinkle of cheese and a light grill to brown the top and voila – yummy frittata for an easy Sunday evening meal. The big question is have I increased my risk of getting cancer by frying in olive oil?

“Exposure to second-hand cigarette smoke or going outside without sun-block is much more likely to cause cancer than burning your cooking oil,” writes fats and oils expert, Laurence Eyres, in the October/November issue of Food New Zealand – the official journal of the NZ Institute of Food Science and Technology. But what about all those cancer causing chemicals – polycyclic aromatic hydrocarbons – that are formed when we burn cooking oil? It’s true that when oil is repeatedly heated to its smoking point it will begin to accumulate cancer causing substances and lose its natural antioxidants. But who uses the same oil over and over again, especially when we’ve burnt it? We usually just heat and eat.

When researchers feed ‘severely heat-abused frying fats’ (more than we would ever do at home) to some poor experimental animals there are ‘very few deleterious effects’. In fact olive oil is especially stable because it is monounsaturated. Extra virgin olive oil is even better than a lower quality olive oil because it has more natural antioxidants to soak up nasty free radicals. And good news for those of us who love New Zealand extra virgin olive oil. Compared to overseas olive oils it has more antioxidants and a higher smoking point, so you can heat it hotter before it starts to burn.