Food Philosophies


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When it comes to nutrition there are a variety of food philosophies each claiming to promote good health. With so much conflicting advice, Josie Cowgill BA(Hons) Dip.ION unravels some of the controversy by analysing seven popular dietary regimes





Basic Principles: The Zone Diet is named so because it is based on the dietary concept of reaching “The Zone” – an expression used by athletes to describe a near euphoric state of maximum physical, mental and psychological performance in which the body is working at peak efficiency.(1) According to Dr Barry Sears, Zone Diet pioneer and author of several books on the subject, the reason people are getting fatter despite the fact that overall fat consumption has declined, is due to excessive carbohydrate consumption, particularly carbohydrates with a high glycaemic index. Too many carbohydrate foods can trigger a rapid rise in blood glucose and a corresponding rise in insulin, an enzyme which converts the excess glucose into fat. Sears claims that meals consisting of 40% of calories from carbohydrate, 30% from protein and 30% from fat provides the ideal balance of macronutrients to maintain normal blood sugar.

General Guidelines: Each meal or snack should aim to contain the 40:30:30 ratios of carbohydrate, protein and fat respectively. Guidance is given on calculating protein requirements and this is spread evenly over three meals and two snacks with no more than five hours between them. Sears divides food into blocks, with protein blocks containing 7 grams, carbohydrate blocks 9 grams, and fat blocks 1.5 grams. Each person is allowed a certain number of blocks of food depending on their weight. All food needs to be weighed or measured to ensure the correct number and ratios of blocks.(2)

Meal Examples:

Breakfast: Bagel with smoked salmon and
low fat cream cheese.
Lunch: Chicken breast with broccoli,
cauliflower and green beans and
1/2 teaspoon of mayonnaise.
Dinner Tofu and vegetable stir-fry.
Snacks: 1/4 cup of low-fat cottage cheese
and 1/2 an apple.
100g low fat yoghurt with no fruit.

Macronutrient ratios:

Carbohydrate: 40% Protein: 30% Fat: 30%

Claims of the Diet: Enhanced mental and physical performance, weight loss, prevention of disease particularly insulin resistance and blood sugar imbalances, anti-ageing.

Critique: In order to calculate the macronutrient ratios correctly it is necessary to weigh all foods, which can be impractical and may lead to obsessive behaviour. Many traditional meals are high in carbohydrates, so eating out may prove difficult. Vegetarians and vegans could develop very repetitive diets due to the limited foods available to them with a high enough protein content. In the long term, high protein diets may put a strain on the liver and kidneys, and contribute to osteoporosis due to its acidifying effect on tissues. Such a diet may also result in constipation and mucus production as many high protein foods are mucus forming.

Lifestyle factors: The importance of exercise is addressed.




Basic Principles: There are various versions of the food combining diet and all have slightly different recommendations. However, the basic premise is that protein requires an acid environment for digestion whilst carbohydrates require an alkaline environment. Thus, if protein and carbohydrate foods are eaten at the same meal, digestion of both will be retarded leading to fermentation and putrefaction. Also included in the guidelines is that acidic foods should not be eaten with starchy foods as acid can neutralise the enzyme salivary amylase, which begins the process of carbohydrate digestion in the mouth.(3) Fruit should be eaten on its own as it digests very quickly in the stomach and may cause fermentation if combined with other foods.

General Guidelines: Meals are eaten either as a combination of protein (fish, meat, poultry, eggs, cheese, beans, pulses, etc) with non-starchy vegetables and salads, or starchy foods (bread, pasta, potatoes, rice etc) with vegetables and salads. Three to four hours should be left between carbohydrate and protein meals in order for the stomach to be empty. Neutral foods such as non-starchy vegetables can be eaten in between if necessary.(4)

Fruit should be eaten on its own as it digests very quickly in the stomach and may cause fermentation if combined with other foods

Meal Examples:

Breakfast: Fruit may be eaten throughout the morning.
Carbohydrate meals: Rice salad or potato soup.
Protein meals: Chicken salad or fish with vegetables.
Snacks: Non–starchy vegetables and salads.

Claims of the diet: Improved digestion and absorption, weight loss, increased energy.

Macronutrient ratios: Depends on whether it’s a carbohydrate or protein meal.

Carbohydrate meal:
Protein: 10% | Carbohydrate: 70% | Fat: 20%

Protein meal:
Protein: 50% | Carbohydrate: 10% | Fat: 40%

Critique: The carbohydrate meals and eating fruit alone could cause blood sugar imbalances for some individuals. Most foods contain a combination of carbohydrate and protein naturally so there is always going to be some conflict in the gut according to this theory. Eating out could be a problem as most traditional meals contain a combination of carbohydrate and protein e.g. fish and chips, sandwiches, chicken curry with rice etc.

Lifestyle Factors: No specific recommendations although tea, coffee, alcohol and cigarettes are not recommended.




Basic Principles: According to advocates of the Palaeolithic diet (Stone Age diet), genetically we have remained the same as our early ancestors and it is millions of years of evolution that have shaped our need for specific nutrients. S Boyd Eaton, an expert in Palaeolithic diets, states that 99.99% of our genes were formed before the development of agriculture about 10,000 years ago.(5) Before this time people were hunter-gatherers eating fruit, vegetables, nuts, seeds, legumes and meat.

Grains and dairy produce were rarely, if ever, eaten. Early man would have had a much more varied range of produce than is available today with typically 100 different species of fruit and vegetables being consumed. Food was eaten within hours of being gathered and was unprocessed and often raw.(6) The dietary changes that have occurred in the last 10,000 years have outpaced our ability to evolve with them and as claimed by this philosophy don’t meet our genetic requirements.

General Guidelines: The diet is based on organic or game meats and fish, fruit, vegetables, legumes, nuts and seeds. Food should be unprocessed and raw or lightly cooked. Grains, dairy produce, refined foods, tea, coffee and alcohol should be avoided.

Meal Examples:

Breakfast: Fruit and nuts.
Lunch: Wild venison with steamed vegetables.
Dinner Wild salmon with salad.
Snacks: Fruit, vegetables, nuts and seeds.

Claims of the diet: Eating like our ancestors should reduce the likelihood of developing degenerative diseases such as diabetes, cancer and heart disease.

Macronutrient ratios: Protein: 30% Carbohydrate: 50% Fat: 20% (may vary according to season, climate and location).

Critique: Truly wild, organic meat is virtually impossible to locate nowadays, the organic meat available being from farmed animals. This meat is totally unlike the meat that was available to the caveman, containing different ratios of lean tissue to fat as well as different types of fat depending on what the animals are fed (some are fed on a grain-based diet which would not have been the case in pre-historic times). Being a vegan or vegetarian on this diet would make it very difficult to obtain adequate protein, vitamin B12 and vitamin D. Although our ancestors may have had periods where there was little or no meat available they would certainly have eaten insects which would have provided them with vitamin B12 and their outdoor lifestyle would have ensured adequate vitamin D from sunlight. Our lifestyles and environment today are so far removed from those of our ancestors that it would be impractical to imitate their diet.

Lifestyle factors: Early man would have been physically active for much of the day so ideally this should be incorporated into the daily routine preferably outdoors in a park or the countryside.




Basic Principles: Macrobiotics, which literally means “large” (macro) “life” (biotics), is based on the theory of “yin” and “yang” -two opposing forces that exist in all things. Examples include day and night, male and female, wet and dry, etc. It was Japanese-born George Ohsawa who first applied the concept of yin and yang to nutrition. Ohsawa was able to work out that when a food is moderate in either “yin” or “yang”, as in most whole foods, the body can maintain or regain good health. However, the effect of foods that are more extreme in either “yin” or “yang” energy (see General Guidelines) is likely to result in emotional instability and physical disease.

Methods of cooking, climate, and season also play an important role in food choices.

General Guidelines: Recommendations for those living in a temperate climate such as Britain and North America include eating mainly whole grains, beans, vegetables and seaweed with smaller amounts of fruit, nuts, seeds and fish. Food should be organic, and fruit and vegetables should be locally grown in season.(7) Those living in tropical regions would include more locally grown fruits and crops while Eskimos would eat mainly fish with very few plant foods, as not many grow in a cold environment.

Meat, eggs and salt, which are extremely “yang” in quality and dairy produce, refined foods, sugar, deadly nightshade vegetables (potatoes, tomatoes, aubergines and peppers), spices, tea, coffee and alcohol, which are extremely “yin” in quality, are not permitted.

Meal Examples:

Breakfast: Well cooked whole grains.
Lunch: Millet with broccoli, onion and leeks.
Dinner Adzuki beans with kombu and carrots.
Snacks: Buckwheat muffin.

Claims of the diet: Can help prevent or ease a wide range of illnesses including heart disease, cancer, diabetes etc.(7)

Macronutrient ratios:
Protein: 15% | Carbohydrate: 70% | Fat: 15%

Critique: The diet may lead to blood sugar imbalance in some individuals due to large amounts of carbohydrates relative to protein. It may not be good for anyone with grain intolerance as whole grains make up a large proportion of the diet. The use of sea vegetables, although health promoting in most people, may aggravate some skin conditions (such as acne and rosacea) due to the iodine content, although this may be beneficial in those with low thyroid function. Macrobiotic based meals contain plenty of fibre and are in harmony with the environment as local/seasonal food is advocated.

Lifestyle factors: Basic recommendations are to live in tune with the environment. Tea, coffee, alcohol and cigarettes should be avoided or kept to a minimum.




Basic Principles: The four blood types present today came into being at different times of our evolutionary history in response to environmental and dietary changes. Type O is the oldest blood type and arose when mankind was a hunter-gatherer. Type A evolved when people became more settled and started cultivating grains around 25000 to 15000 BC. Type B developed in the herdsmen of the Himalayas as well as in Asia around 10 to15000 BC. Type AB is the most recent and rarest blood type to appear and emerged from the inter-mingling of Type A and B around 900 AD.(8)

General Guidelines: Foods are divided into headings under “highly beneficial”, “neutral” and “avoid” with detailed lists for each blood type. Below are examples of some of these foods; however, to follow the diet correctly the book Eat Right for Your Type, by Dr Peter D’Adamo (Putnam’s Sons) is essential reading.


Beneficial: Red meat, seafood, sea vegetables, onions.
Neutral: Poultry, chickpeas, brown rice, apples.
Avoid: Wheat, hard cheeses, lentils, avocados.

Meal Examples:

Breakfast: Puffed rice with soya milk and a poached egg.
Lunch: Chicken salad with walnuts and two plums.
Dinner Baked fish with green beans.


Beneficial: Trout, adzuki beans, lentils, soya products, buckwheat, carrots, pineapple.
Neutral:Poultry, yoghurt, peas, millet, lettuce, apples.
Avoid:Red meat, hard cheeses, kidney beans, the nightshade family of foods (potatoes, tomatoes, aubergines and peppers).

Meal Examples:

Breakfast: Oatmeal with soya milk.
Lunch: Bean soup with salad.
Dinner Baked fish with vegetables.



Beneficial: Lamb, yoghurt, brown rice, cabbage, bananas.
Neutral:Beef, trout, peas, pasta, onions, apples.
Avoid:Chicken, sunflower seeds, lentils, corn, buckwheat, olives.

Meal Examples:

Breakfast: Granola with skimmed milk and banana.
Lunch: Cheese on spelt bread with green salad.
Dinner Lamb stew with brown rice and steamed vegetables.



Beneficial: Lamb, mackerel, feta, millet, parsnips, grapes.
Neutral: Swordfish, Brazil nuts, pasta, lettuce, apples.
Avoid: chicken, milk, adzuki beans, buckwheat, corn, bananas.

Meal Examples:

Breakfast: Granola with soya milk.
Lunch: Tabbouleh.
Dinner Salmon with brown rice and green salad.

Claims of the diet: Weight loss, avoidance of allergies and intolerances, benefits the immune system, reduces inflammation and digestive problems.

Macronutrient ratios: This is variable depending on foods chosen but Type O is recommended a high protein, low carbohydrate diet whilst Type A needs a high carbohydrate, low protein diet. Type B and AB should have a balance of carbohydrate and protein.(8)

Critique: As long as people have access to a sufficient variety of the foods they are permitted to eat, there should be no problem with following the overall principles of the diet. However, adhering to the recommendations strictly could be difficult as there are long lists of foods to include or avoid. These foods could be hard to commit to memory and may result in obsessive behaviour. Problems could arise if family members have different blood types or if a Type O is vegetarian or vegan.

Lifestyle factors: Exercise and response to stress are incorporated in the regime, along with beneficial supplements and herbs for each blood type.




Basic Principles: “Biologically people are to live on raw, untreated, unprocessed natural foods from the plant kingdoms.”(9) The belief of raw food advocates is that whilst raw foods contain vitamins, minerals, enzymes and essential fatty acids and are essentially “alive”, cooking foods destroys these life-giving properties which may result in disease. Some advocates eat 100% raw foods while others eat a high proportion of raw foods with some cooked foods.

There are more extreme groups such as fruitarians who eat only fruit.

General Guidelines: The dietary regime consists of fruit, vegetables,
salads, nuts, seeds, herbs, sea vegetables, spices, flowers, fungi, sprouted beans, pulses and grains, and cold pressed vegetable oils.

Meal Examples:

Breakfast: Fruit smoothie with blended nuts.
Lunch: Vegetables in an avocado and almond sauce with nori flakes.
Dinner Salad of sprouted pulses and grated vegetables with raw houmous (made with sprouted chickpeas).
Snacks: Nuts, seeds, fruit, vegetables.

Claims of the diet: Increased energy, mental clarity, improved immunity, weight normalisation, better skin, hair, nails and brighter eyes and a decreased need for sleep.

Macronutrient ratios:
Protein: 15% | Carbohydrate: 60% | Fat: 25%

Critique: Some nutritionists believe that too much raw food can have a cooling effect on the body, leaving it depleted in the long term. Such a diet may be easier to follow and more suitable in the summer in temperate climates or in warm countries where plenty of fresh food is available. However, it may be beneficial for short periods while detoxifying the body, especially during spring, summer or autumn. Blenders, food processors and sprouting jars become necessities instead of saucepans and a cooker. Eating out would be restricted to restaurants with good salad bars.

Lifestyle factors: A chemical-free existence, such as using natural toiletries and cleaning products, and eating organic food, is recommended.




Basic Principles: This dietary regime is purely aimed at people wishing to lose weight. The Weight Watchers website claims following their food plan encourages participants to eat a healthy, well-balanced, interesting diet, including some of their favourite foods. Each food is given a number of points depending on the amount of calories and saturated fat it contains. The idea is that people will be inclined to choose lower fat, healthier foods because these have fewer points, so more can be eaten. Support and encouragement are key parts of the plan with weekly group sessions provided for members to be weighed and to exercise together.(10)

General Guidelines: Individuals are allocated a number of food points depending on their age, sex and current weight. More points can be “earned” by exercising. The concept is that people can eat what they want as long as they don’t exceed their allocated number of points. Points can be saved up for special treats. Lots of meal examples are provided and the number of points in many supermarket foods and restaurant meals are supplied, as are recording charts.(11)

Meal Examples:

Breakfast: Cornflakes with skimmed milk.

Lunch: Two slices of wholemeal toast with low-fat cheese and a salad.
One apple.
Dinner Chicken with a jacket potato and vegetables. Half a tin of fruit and a meringue nest.
Snacks: Weight Watchers chocolate bar.
Half a pint of skimmed milk for tea and coffee.

Claims of the diet: Steady weight loss and healthier eating habits while still allowing treats, thus avoiding feelings of denial.

Macronutrient ratios:
Protein: 30% | Carbohydrate: 50% | Fat: 20%

Eating plenty of fruit and vegetables and drinking water are all encouraged while treats such as the odd glass of wine or Weight Watchers snack bars are allowed


Getting to know the number of points in different amounts of food may take time although plenty of guidance is given in the literature. There are various packaged foods and ready meals which come under the Weight Watchers brand and this makes it easier to count points but many of the foods are processed and contain artificial sweeteners and additives. Eating plenty of fruit and vegetables and drinking water are all encouraged while treats such as the odd glass of wine or Weight Watchers snack bars are allowed. Drinking a pint of skimmed milk a day either in cereal, tea or coffee or as a milky drink is recommended in order to meet calcium requirements, which could be a problem in those with dairy intolerance.

The diet could potentially become obsessive for some individuals and could lead to feelings of guilt if points are exceeded. It seems to promote the idea that exercise is something that is undertaken so that more calories can be consumed.

On a positive note, support from others is part of the programme and this has been shown to play an important role in helping people stick to the regime. People are also encouraged to continue to support each other after the weight has been lost.

Lifestyle factors: Exercise is an inherent part of the programme.




Clearly there are many different diets all claiming to improve health in one way or another. The ones mentioned in this article are just a few of the many food philosophies that people turn to in their search for improved well-being. Invariably, they are likely to be successful due to the fact that they all encourage healthier food choices and do not include junk foods, fast foods or highly processed foods (except for the Weight Watchers diet).

The literature on each of the diets appears to put the message across that the guidelines should be followed rigidly and that other diets do not work as well. None of them suggest that they may not be suitable for some people. In reality there is no one diet that is going to suit everyone all the time; we are all biochemically different and have reached our current state of health through wide-ranging genetic, dietary, lifestyle, environmental and psychological factors. Even when one specific diet initially results in health improvement this does not necessarily mean that it should be followed stringently for life.

It is the role of a nutritional therapist to understand the potential uses and benefits of different ways of eating. This can then be used in conjunction with their knowledge of how the human body works under different circumstances to devise nutritional protocols for individual clients. This may involve following one protocol for a limited period of time or using components of several protocols to create a diet suitable for an individual’s circumstances at that time. Changes may need to be made gradually at a pace agreed with the client.

Suitable exercise and relaxation regimes should be encouraged as part of the healing process at whatever level the client is capable of. Psychological components behind any symptoms should not be overlooked. Any strategy should be reviewed and revised as health and circumstances change.

Anyone wishing to follow one of the mentioned diets would be advised to read the appropriate literature, and in the case of ill health, to consult a nutritional therapist or discuss the proposed diet with their doctor.


Babel, K. The Zone: Sound Advice or Another Diet Craze? Nutrition Science News, January 1997.
Sears, B. Enter the Zone, Harper Collins Publishers, 1995.
Shelton, HM The Necessity of Proper Food Combining, Dr Shelton’s Hygienic Review.
Diamond, Harvey and Marilyn. Fit For Life, Bantam Books, 1987
Eaton, SB et al. An Evolutionary Perspective Enhances Understanding of Human Nutritional Requirements. Journal of Nutrition 1196;126:1732-40.
Challem, J. Paleolithic Nutrition: your future is in your dietary past. Nutrition Science News, April 1997.
Kushi Institute website, What is Macrobiotics?
D’Adamo PJ, Whitney, C. Eat Right for Your Type, G.P. Putnam’s Sons, 1996.
Fresh Network:
Weight Watchers:
Weight Watchers Pure Points, Books and Shoppers Guide.


D’Adamo PJ. Cook Right for your Blood Type, GP Putnam’s Sons, 1998.
Pitchford, Paul. Healing with Whole Foods, North Atlantic Books, 1993.
Cowmeadow, Oliver. Yin and Yang – A Practical Guide to Eating a Balanced and Healthy Diet, The Cornish Connection, 1990.
Haas, E. Staying Healthy with Nutrition, Celestial Arts, 1992.
Kenton, Leslie and Susannah. Raw Energy, Vermillion, 1994.
Crawford, Michael and March, David. Nutrition and Evolution, Keats, 1995.

Josie Cowgill is a nutritional therapist working in West London. As well as seeing clients for a range of health problems she is a tutor and lecturer at the Institute for Optimum Nutrition, runs talks and workshops on nutrition and cookery, and writes articles for magazines.

The Institute for Optimum Nutrition is an independent educational charity.
Registered company number 2724405, registered charity number 1013084