People often ask me why we nutritionists keep changing our minds! One year, carbohydrate is wonderful, the next year it's not. One year, fat is a no-no, the next year, it's only saturated fat that we should worry about, the other fats are ‘good' fats that are OK to eat and enjoy. Protein was ‘forgotten' for some years, now it's back and considered important for satiety and weight loss.

Fashions in foods

And the same happens with foods. Eggs make a good example. They were off the Acceptable list for many years due to their high cholesterol. Anyone with a high cholesterol was advised to limit them to only 2 a week. Now it's OK to eat an egg a day if you wish (and many people love an egg on toast for breakfast). As long as you don't drown it in butter or cream! The body regulates the cholesterol it makes in response to what you eat. But it can't cope with the saturated fat that's already a big problem in our daily diets.

However I rationalise and justify these paradigm shifts, there's no doubt that nutrition changes. It evolves, it twists and turns, it often swings back to an earlier position. This is confusing for consumers but hardly surprising for a new science that is blended from biochemistry, physiology, medicine, food science and the culinary arts. As new terms and new discoveries keep popping up, there are shifts in thinking on many issues.

Is it simple or complex?

Just five years ago, we dietitians were still talking 'simple' and ‘complex' carbohydrates. How naive was that thinking? Thanks to research from the Glycemic Index, we now have a better understanding of what happens to foods like bread, potato, rice and pasta once we've ingested them. Some are fast, some are slow. Sugar surprisingly is moderate. Some types of rice are fast, some are moderate too. It's got nothing to do with a simple or a complex structure - it's much more complex than that (forgive the pun!).

The golden rules

So should you NOT take on board the latest advice? Even though nutrition changes at the edges, the basics remain similar and I often remind people of these ‘golden rules' or 'dietary commandments' as I like to call them. They're worth remembering! For a healthy diet, aim to:

• eat plenty of vegetables and fruit (note the order - we should eat TWICE as many vegetables/salads as fruit)
• cut back on sugar and sugary drinks go easy on salt
• choose whole grains and high fibre breads and cereals you don't need heaps of fat; just an average amount of fat from oil, avocado and nuts will keep your body in good working order
• steer clear of overly-processed and refined foods
• eat more fresh and home-prepared meals
• be moderate with alcohol
• eat a little of what you like and moderation in most things.

Sound familiar? It's probably what your Grandma would have told you.