A general comment to start.
As you read on you will be aware that we should be heading towards a more plant-based diet. Possibly the ideal way of eating for the world would be to adopt the lacto-ovo-vegetarian style of eating where eggs and dairy products are still consumed but other forms of animal protein are avoided. This has significant social implications such as having special meals prepared when visiting, the increased time it takes to prepare fruit and vegetables and most especially be seen as different from the herd.

Become an opportunistic vegetarian. Where ever possible eat vegetarian and if meat is served, have it. Alternatively, a good compromise is not to totally remove meat from your diet but to greatly reduce consumption say to once a week or to use meat as a garnish to largely vegetable dishes. That way you get the best of both worlds: you are not seen as different but you are making a significant contribution to improving sustainability. An excellent discussion of this is in the third section, "Foraging" of Michael Pollan's book, "An Omnivore's Dilemma" (Pollan 06 -1).

1. The starter pack.
Diets are often made to seem complicated with lots of confusing numbers and portion sizes. People become very concerned that they are not getting the right mix, particularly when they feel less than their best, often resorting to tonics and pills. It is quite usual for most people to feel a little tired or less than your best some of the time. This is not a cause for concern. Don't be tempted to rush into miracle diets and cures. The approach here has been clearly shown by large studies to give the best long term health. If you are overweight reduce your food intake very slowly over a period of months. Crash diets rarely work in the longer term. Remember that exercise no matter what your weight is the best thing you can do for yourself.

1.1 Increase the amount of fruit and vegetables that you eat (for a standard 2000 Kcal diet).

• Fruit: eat at least two full sized pieces of fruit or their equivalent such as apples, oranges, pears a day. Other smaller fruits such as grapes, plums, Kiwi fruit, work out roughly the volume that would be equivalent to that of an apple or orange and substitute that. (This corresponds to two cups or more.) Canned or frozen fruits are also OK.
   
• Vegetables: your main meal should have at least two and a half and preferably more cups of vegetables a day. Eat the widest range of vegetables. The greater the range, the greater the benefit - yellows, deep greens and reds. Two cups of leafy greens is equivalent to one cup of vegetables.
   
• A special point about potatoes: while the humble potato is a vegetable it doesn't have many positive qualities beyond providing energy. It is low in fibre and has a high glycaemic index and load. It is not recommended that you pad out your vegetable quota for the day with these by devouring fries or crisps. They don't count beyond a small serving. You will do just as well eating cakes, cookies or white bread.

1.2 When you eat cereal based foods, make sure it is wholegrain (or wholemeal).

• Eat at least two slices of wholegrain bread a day.
   
• Have cereal in the morning but make sure it is whole grain such as shredded wheat, whole wheat biscuits, porridge, un-toasted muesli and the like.
   
• Avoid white bread and cereal products that have little fibre.

1.3 Limit your intake of meats - high protein intake does not give you big muscles.

• Don't sit down to a predominantly meat meal. Use meat as a garnish for salads, curries, stir-frys. Look at the way traditional Indian and Asian food is served: these dishes are largely vegetable with either a small amount of meat or none at all.
   
• If you do eat meat, avoid eating the fat. Cut it off and throw it away. Remember that even if the fat melts into the sauce or gravy, it is still very bad for you.
   
• Chicken meat has less fat than red meat as long as you avoid eating the skin.

1.4 Don't consume at lot of dairy products - dairy foods are not health foods.

• Don't consume a lot of milk, around two cups or less, and make sure it is low fat.
   
• Don't use butter. Make sure your margarine is low in transfats.
• Eat ice cream only as an occasional treat.
   
• Either avoid or eat very sparingly cheese, particularly hard cheeses.

1.5 What to eat as snacks?

• Nuts or dried fruit are good.
   
• Whole wheat crackers spread with hummus, pesto or tapanade.

1.6 Limit your intake of manufactured foods including take-aways and restaurant meals - save yourself a fortune.

• Most of these foods are designed to taste really nice using ingredients to improve sales and not your health. Remember if you make your own you save heaps and heaps of money. (The best things in life are free.)
   
• Things to particularly avoid: soft drinks, potato crisps, food bars of all types, highly processed foods (they are easy to detect because they have long lists of ingredients - if a food has more than 10 it should be definitely avoided.)
   
• The less you have to do in preparation for a pre-prepared meal, the less likely it is to be good for you and the more likely it will cost you heaps.

1.7 Limit consumption of fruit juice

• Contrary to a lot of advice, fruit juice (and drinks) are not health foods. It is far better to eat the fruit itself. Fruit juice adds to the obesity problem if consumed in volumes greater than 500mL per day. Unlike whole fruit, it is much more acidic and along with the sugars, will damage your teeth, particularly if sipped without a straw. 
   
• The best advice is to drink tap water for fluids and eat fruit as a whole foods.

1.8 Drink tap water rather than drinks from bottles or cans.

• There is nothing wrong with tap water and it comes free. Despite many claims that bottled water is better for you, there is no reputable evidence to back this claim, many of which are generated by the people who produce the bottled water. Don't be fooled.
   
• Many soft drinks are loaded with sugar which will make you fat and damage your teeth.
   
• Perhaps the worst offenders are cola type drinks which in addition to all the other problems listed already are even more acidic. They have led to an epidemic of dental caries, particularly if they are sipped without a straw.
   
• Sports drinks don't give any advantage over tap water but they will damage your teeth and your budget.

Useful easy-to-remember facts.

• Fats whether they be solid or liquid such as vegetable oils are all fattening, containing 9Kcal/g (270Kcal/oz) Don't guzzle the salad dressing if you want to stay thin, even small amounts are fattening.
   
• Alcohol is also fattening having 7Kcal/g (210Kcal/oz). It is the alcohol in beer (and other alcohol containing drinks), not the other carbohydrates that stack on the weight.
   
• High protein diets are not useful as the extra protein is simply burnt up by the body, adding to your fat stores and not your muscles.
   
• An additional 100 Kcal/day (400 Kjoules/day) about half a small bag of potato crisps will increase your weight by 5kgs (10lb) in a year.
   
• Most snack foods are loaded with fats, sugars and/or salt. Almost none of them are good for you beyond the occasional treat. Added vitamins and trace nutrients don't change their underlying badness. (A wolf in sheep's clothing.)
   
• Exercise is of the utmost importance no matter what your weight. Overweight people who exercise regularly do better then thin people who don't exercise at all. (Being the correct weight and regularly exercising is even better.)

If you stick to these simple principles your body will do the rest. There is a very simple test to measure whether you are consuming the right amount of food provided you follow the food mix outlined above: stand on the scales. (Many scales in shopping centres will also measure your body mass index as well. ) This diet will keep you thin and healthy and definitely add to your well-being and happiness.

You also have a built in indicator to show you if you are getting the right amount of fluid. Your urine should be paler than the background colour of this web page. If it is darker, drink more. It is unnecessary to drink large volumes if your urine is the right colour. Remember that sugary or acidic soft drinks if sipped over any length of time will wreck your teeth. This includes all types of sports drinks.

(Davies 06) Neal Davies. Polyphenols and fruits: importance of glycosylation, chirality, food processing and organic farming. AAAS February 06 Meeting. Downloadable from www.organic-center.org.

(Key 06) Timothy J. Key, Paul N. Appleby and Magdalena S. Rosell. Health effects of vegetarian and vegan diets. Proceedings of the Nutrition Society 2006);65:35–41

(Messina 03) Virginia Messina, Vesanto Melina, Ann Reed Mangels. A new food guide for North American Vegetarians. Can J Prac Res 2003;63:82-86

(Mozaffarian 04) Dariush Mozaffarian, Eric B Rimm, David M Herrington. Dietary fats, carbohydrate, and progression of coronary atherosclerosis in postmenopausal women. American Journal of Clinical Nutrition 2004; 80:1175-1184.

(Nestle 06) Marion Nestle. What to eat. 2006, North Point Press.

(Pollan 06-1) Michael Pollan. An Omnivore's Dilemma. 2006 Bloomsbury, Chapter 15, The Forager, p 275.

(Pollan 06-2) Michael Pollan. An Omnivore's Dilemma. 2006 Bloomsbury, Chapter 9, Big organic, p 134.

(Saxelby 06) Catherine Saxelby. Nutrition for life. 2006 Hardie Grant Books

(Tickell 04) John Tickell. The Great Aussie Diet. 2004 Boomerang Books.