In nutrition, diet is the sum of food consumed by a person or other organism. The word diet often implies the use of specific intake of nutrition for health or weight-management reasons (with the two often being related). Although humans are omnivores, each culture and each person holds some food preferences or some food taboos. This may be due to personal tastes or ethical reasons. Individual dietary choices may be more or less healthy.
Complete nutrition requires ingestion and absorption of vitamins, minerals, and food energy in the form of carbohydrates, proteins, and fats. Dietary habits and choices play a significant role in the quality of life, health and longevity.
Religious and cultural dietary choices
Some cultures and religions have restrictions concerning what foods are acceptable in their diet. For example, only Kosher foods are permitted by Judaism, and Halal foods by Islam. Although Buddhists are generally vegetarians, the practice varies and meat-eating may be permitted depending on the sects. In Hinduism, vegetarianism is the ideal. Jains are strictly vegetarian and consumption of roots is not permitted.
Types of diets
An individual’s diet is the sum of food and drink that he or she habitually consumes. Dieting is the practice of attempting to achieve or maintain a certain weight through diet. People’s dietary choices are often affected by a variety of factors, including ethical and religious beliefs, clinical need, or a desire to control weight.
Not all diets are considered healthy. Some people follow unhealthy diets through habit, rather than through a conscious choice to eat unhealthily. Terms applied to such eating habits include “junk food diet” and “Western diet”. Many diets are considered by clinicians to pose significant health risks and minimal long-term benefit. This is particularly true of “crash” or “fad” diets – short-term weight-loss plans that involve drastic changes to a person’s normal eating habits.
- Fruitarian diet: A diet which predominantly consists of raw fruit.
- Lacto vegetarianism: A vegetarian diet that includes certain types of dairy, but excludes eggs and foods which contain animalrennet. A common diet among followers of several religions, including Hinduism and Jainism, based on the principle of Ahimsa (non-harming).
- Lacto-ovo vegetarianism: A vegetarian diet that includes eggs and dairy.
- Vegan diet: In addition to the requirements of a vegetarian diet, vegans do not eat food produced by animals, such as eggs, dairy products, or honey.
· Flexitarian diet: A predominantly vegetarian diet, in which meat is occasionally consumed.
- Kangatarian: A diet originating from Australia. In addition to foods permissible in a vegetarian diet,kangaroo meat is also consumed.
- Pescetarian diet: A diet which includes fish but not meat.
- Plant-based diet: A broad term to describe diets in which animal products do not form a large proportion of the diet. Under some definitions a plant-based diet is fully vegetarian; under others it is possible to follow a plant-based diet whilst occasionally consuming meat.
Diets followed for medical reasons
People’s dietary choices are sometimes affected by intolerance or allergy to certain types of food. There are also dietary patterns that might be recommended, prescribed or administered by medical professionals for people with specific medical needs.
- Best Bet Diet: A diet designed to help prevent or mitigatemultiple sclerosis, by avoiding foods with certain types of protein.
- Colon cancerdiet: Calcium, milk and garlic are thought to help prevent colon cancer. Red meat and processed meat may increase risk.
- Diabetic diet: An umbrella term for diets recommended to people with diabetes. There is considerable disagreement in the scientific community as to what sort of diet is best for people with diabetes.
- DASH Diet(Dietary Approaches to Stop Hypertension): A recommendation that those with high blood pressure consume large quantities of fruits, vegetables, whole-grains and low fat dairy foods as part of their diet, and avoid sugar sweetened foods, red meat and fats. Promoted by the US Department of Health and Human Services, a United States government organisation.
- Elemental diet: A medical, liquid-only diet, in which liquid nutrients are consumed for ease of ingestion.
- Elimination diet: A method of identifying foods which cause a person adverse effects, by process of elimination.
- Gluten-free diet: A diet which avoids the proteingluten, which is found in barley, rye and wheat. It is a medical treatment for gluten-related disorders, which include coeliac disease, non-celiac gluten sensitivity, gluten ataxia, dermatitis herpetiformis and wheat allergy.
- Healthy kidney diet: This diet is for those impacted with chronic kidney disease, those with only one kidney who have a kidney infection and those who may be suffering from some other kidney failure.This diet is not the dialysis diet, which is something completely different. The healthy kidney diet restricts large amounts of protein which are hard for the kidney to break down but especially limits: potassium and phosphorus-rich foods and beverages. Liquids are often restricted as well—not forbidden, just less of.
- Ketogenic diet: A high-fat, low-carb diet, in which dietary and body fat is converted into energy. It is used as a medical treatment for refractoryepilepsy.
- Liquid diet: A diet in which only liquids are consumed. May be administered by clinicians for medical reasons, such as after a gastric bypass or to prevent death through starvation from a hunger strike.
- Specific Carbohydrate Diet: A diet that aims to restrict the intake of complex carbohydrates such as found in grains and complex sugars. It is promoted as a way of reducing thesymptoms of irritable bowel syndrome (IBS), Crohn’s disease,ulcerative colitis, coeliac disease and autism.
Weight control diets
A desire to lose weight is a common motivation to change dietary habits, as is a desire to maintain an existing weight. Many weight loss diets are considered by some to entail varying degrees of health risk, and some are not widely considered to be effective. This is especially true of “crash” or “fad” diets.
Many of the diets listed below could fall into more than one subcategory. Where this is the case, it is noted in that diet’s entry.
· Intermittent fasting: Cycling between non-fasting and fasting as a method of calorie restriction.
- Body for Life: A calorie-control diet, promoted as part of the 12-weekBody for Life
- Cookie diet: A calorie control diet in which low-fatcookies are eaten to quell hunger, often in place of a meal.
- The Hacker’s Diet: A calorie-control diet fromThe Hacker’s Diet by John Walker. The book suggests that the key to reaching and maintaining the desired weight is understanding and carefully monitoring calories consumed and used.
- Nutrisystems Diet: The dietary element of the weight-loss plan from Nutrisystem, Inc. Nutrisystem distributes low-calorie meals, with specific ratios of fats, proteins and carbohydrates.
- Weight Watchers diet: Foods are assigned points values; dieters can eat any food with a points value provided they stay within their daily points limit.
Very low calorie diets
A very low calorie diet is consuming fewer than 800 calories per day. Such diets are normally followed under the supervision of a doctor.
“Zero-calorie diets are also included”
- Breatharian diet: A diet in which no food is consumed, based on the belief that food is not necessary for human subsistence.
- KE Diet: A diet in which an individual feeds through afeeding tube and does not eat anything.
· Atkins diet: A low-carbohydrate diet, popularised by nutritionist Robert Atkins in the late-20th and early-21st centuries. Proponents argue that this approach is a more successful way of losing weight than low-calorie diets; critics argue that a low-carb approach poses increased health risks. Thе Atkinѕ diеt соnѕiѕtѕ оf fоur рhаѕеѕ (Induсtiоn, Bаlаnсing, Finе-Tuning and Mаintеnаnсе) with a grаduаl inсrеаѕе in соnѕumрtiоn оf саrbоhуdrаtеѕ аѕ thе реrѕоn gоеѕ thrоugh the рhаѕеѕ.
- Dukan Diet: A multi-step diet based on high protein and limited carbohydrate consumption. It starts with two steps intended to facilitate short term weight loss, followed by two steps intended to consolidate these losses and return to a more balanced long-term diet.
- ITG Diet: A 3-step diet based on limiting carbohydrate consumption combined with low fat protein to maintain muscle, with the objective of returning to a healthy balanced diet for long term weight maintenance.
- South Beach Diet: Diet developed by the Miami-based cardiologist Arthur Agatston, M.D., who says that the key to losing weight quickly and getting healthy isn’t cutting all carbohydrates and fats from your diet. It’s learning to choose the right carbs and the right fats.
· McDougall’s starch diet is a high calorie, high fiber, low fat diet that is based on starches such as potatoes, rice, and beans which excludes all animal foods and added vegetable oils. John A. McDougall draws on historical observation of how many civilizations around the world throughout time have thrived on starch foods.
Food occupies a central place in our daily life. It supplies all essential nutrients necessary for our existence, and is the source of our physical and mental energy. Since the earliest times, people have been aware that a poor or unbalanced intake of food and drink can lead to the onset, progress or persistence of many common diseases. In fact, most chronic disorders of our time result in part from malnutrition in one form or another. Diabetes, obesity, heart disease, inflammatory diseases, some skin disorders and cancer can trace their origin back to poor or unwise consumption of food – too much salt or fat; too little fibre; not enough fruit and vegetables; bad eating habits, etc. Many of the early observations have since been unequivocally confirmed by studies carried out by present-day medical research. For example, cancer is, in many if not most cases, linked to the type of food consumed by the person afflicted: specifically the nature of the fat and sugar consumed regularly, and in abnormally large amounts. However, the other side of the coin, the use of diet to improve health, promote recovery from disease, and prevent disorders from developing is enjoying a revival of interest. Long accepted as one of the pillars of Lifestyle Factors , this therapeutic approach is known as dietotherapy. Evidence is mounting that changes to a personʼs diet is capable of reversing the progression of many chronic diseases, and this has lead to renewed interest in the technique. Again, Hippocrates thought of it first: “Let your food be your medicine, and medicine be your food.” Instead of being an afterthought when treating a particular disorder, changes and improvement of diet is now being considered for a place at the forefront of therapy.
What is the difference between dietetics and dietotherapy?
Dietetics is the scientific study of nutrition, or the food and drink we consume – our diet – on a regular daily basis. The reverse, the study of how food, or particular components of it, can contribute to the long-term treatment of chronic ailments, is called dietotherapy. In practice, dietotherapy involves encouraging a person with a chronic disorder, brought on by a faulty or imprudent personal lifestyle, to consciously adopt reasonable and realistic changes to his or her diet, in order to reverse the progress of the disorder. The aim of such dietary changes is to restore equilibrium or harmony to the qualities involved in the personʼs temperament. Dietotherapy is a major therapeutic option, along with cupping, herbal medication (or phytotherapy) and massage. As with all forms of treatment, it respects Physis, the bodyʼs innate capacity for self-healing: “the doctor within us all”. It is an approach to health maintenance and disease alleviation which is completely safe, and, if carried out properly, free from any adverse consequences. By supporting and enhancing Physis, it restores the personʼs intrinsic harmony between the qualities. In most cases, the actual type of food or its nutritive value is not important; it is its ability to reverse the disordered qualities that have lead insidiously to the chronic ailment in the first place. The consumption of specific foods is encouraged, and the omission of deleterious foods discouraged.
Nature of food
Food, whether meat, vegetables, fruit, grains, etc., is made up of five major components: proteins, carbohydrates, fats, minerals and water. It has allocated different qualities to each of these components:
- Proteins: an overall quality of dryness, but with some degree of either heat or coldness, depending on the source of the protein.
- Carbohydrates: an overall quality of moistness, but with some degree of heat or coldness, also depending on the source of the carbohydrate.
- Fats: an overall quality of heat, with different degrees of moistness, and minimal amounts of dryness and coldness.
- Minerals: an overall quality of coldness and dryness.
- Water: an overall quality of moistness.
This means that over a period of time the personʼs overall internal qualities are affected to a greater or lesser extent by the qualities of the food consumed. It also follows that if a personʼs qualitative balance is disturbed to any substantial degree, then this can be reversed or corrected, and balance restored, by consuming food with certain qualities. It therefore considers that we are all affected by both the quantity of food consumed, but by the qualitative nature of the components it contains.
Anything consumed regularly and deliberately by mouth can be divided into different categories. Each of these can affect a personʼs health, positively or negatively.
The food we consume to provide routine nutrition and energy, and which are made up of the components identified above. When we take this, no real changes to the person occur, or are expected, apart from alleviation of hunger. The body extracts from the food what it can use and returns to the environment what it cannot use, together with any waste material or products of metabolism.
- Herbs and spices
These are often added to food to make it more palatable or attractive, and at the same time their medicinal properties contribute towards improving a personʼs general health. Onions, garlic, ginger and almonds fall into this category.
These are substances which are used for medical reasons, but which have nutritive content. Teas made from herbs like peppermint, chamomile or rooibos are examples. A number of foods are able to boost the immune system. Nutriceuticals fall into this category.
These substances change specific functions in the personʼs body. These can be artificial or synthetic chemicals, or extracts from animal, plant or fungi which are biologically active. These latter substances may be chemically modified for increased effect, better tolerance, longer duration of action, or commercial, patent-related reasons. Modern medicine is largely based on these agents. Many pharmaceutics are supplements, such as vitamins and micro-nutrients. The new science of ʻorthomolecular medicineʼ is one form of pharmaceutics. This includes single chemical entities like arginine, MSM and omega-3, which boost particular functions in the body.
It has also classified different items of food into whether they are qualitatively heating or cooling, coupled to whether they are moist or dry. So there are specific foods which are heating, but with different levels of either dryness or moistness. Similarly, there are other foods which are cooling, but with either dryness of moistness.
The concept of the qualities of heating and cooling, moistness and dryness, is linked to the effect of different foods have on the personʼs bodily metabolism and formation of the humours. Heating foods will increase the bodyʼs basic metabolic rate, and cooling foods will have the opposite effect. For some diseases, like rheumatic disorders, heating foods should be used. For other disorders, like hepatitis, cooling foods are more beneficial.
Heating foods and spices confer a number of benefits:
- They increase the production of digestive enzymes in the gut
- They help the body digest food efficiently
- They promote the assimilation of micro-nutrients (vitamins, co-factors, minerals) into the body
- They increase the metabolic rate in body cells
Another factor is the heavy demand made upon the bodyʼs energy status by the digestive process. Eating food spiced with the heating spices ginger, cumin and cinnamon boosts the production of digestive enzymes dramatically. A balanced diet including heating foods is essential for the effective digestion of nutrients, and their subsequent elimination. If the bodyʼs innate heat is reduced, then digestion, absorption and metabolism will be impaired, together with the elimination of waste products. This will result in a build up of the qualities of coldness and dryness. The South African diet typically contains many foods which are cold in nature, like yogurt, cold drinks and salads, or drying in nature, like large amounts of red meat. This leads to the opposite state required for the maintenance of an ideal body temperament of Hot and Moist. Most chronic diseases arise due to an excess of coldness and dryness, with corresponding loss of body heat.
Dietotherapy and temperament
Temperament is an important feature of a person, which defines his or her uniqueness. It is an indispensible characteristic, important in diagnosis and treatment.
The mian aspects are:
- Personality characteristics, including emotional features
- Personal habits regarding regular diet, sleeping patterns, physical exercise and rest
- Physiological characteristics, including age and gender, and the efficiency of excretion mechanisms
- Physical demeanour, appearance and bodily physique All foods possess their own unique temperament, made up of a combination of qualities.
- Protein, a major component of a balanced diet, is predominantly hot, with the second quality being either dry or moist, depending on the particular food.
- Fats possess an overall quality of heat also, with different degrees of moistness, but little dryness and coldness.
- Carbohydrates are predominantly moist, with some being hot and others cold as the second quality. Dryness is least.
- Minerals or electrolytes are invariably cold and dry.
- Water, not unexpectedly, is predominantly cold and moist.
This division of different foods according to temperament and qualities is important for dietotherapy. If a disease is characterised by having certain qualities which have brought disharmony to the person, then treatment generally aims to restore harmony by counteracting the imbalance in qualities. For example, a disorder like acne, which is an imbalance in the Dry and Hot qualities, is treated in dietotherapy by foods which have moistness and coldness as their primary qualities. Likewise, sinusitis, which is usually a Cold and Moist condition, will respond more to foods which are hot and dry qualitatively. The planning of a suitable diet for someone with a particular ailment therefore requires (a) identifying the qualities linked to the ailment, and (b) consuming food which redress the balance in qualities.
The table below summarises a number of common foods and their particular temperament (qualities):
|Temperament (Qualities)||Typical foods|
|Hot and Moist||Liver, mutton, turkey, ginger, olives, bananas, mangos, peaches, almonds, wheat products, rye, cheese, sunflower oil, pepper, turmeric, green tea, honey, chocolate, licorice, most cereals.|
|Cold and Moist||Duck, rabbit, cucumber, butternut, pears, figs, melons, apples, cranberries, rice, semolina, corn flour, milk and its products (butter, custard, shakes), coriander, cumin, vanilla, rose syrup.|
|Hot and Dry||Chicken, shellfish, game birds, red/green peppers, oily fish, garlic, onions, grapes, mustard, cashew and pecan nuts, eggs, cinnamon, cloves, nutmeg, chillies, peri-peri, garlic, alcohol.|
|Cold and Dry||Beef, biltong, white fish, pork, cabbage, cauliflower, tomatoes, sweet potatoes, mielie, mushrooms, citrus fruits, avocados, peanuts, beans, samp, yogurt, basil, prunes, black tea, coffee, vinegar.|
Dietotherapy and maintaining good health
Advises that a person should try to eat according to his or her temperament. In this way, Physis is supported, and the risk of developing a chronic disorder of Lifestyle is reduced.
- Someone with a predominantly sanguinous temperament should go for cold and dry foods which do not increase the Hot and Moist qualities. A diet with balanced or equal amounts of protein, fruit and vegetables salads should be selected.
- If a person is predominantly phlegmatic in nature, then food with Hot and Dry qualities should favour high-fibre fruit and high-protein items like chicken, eggs, sea-foods and liver. Onion and garlic intake should be increased, an herbs like fenugreek, saffron and cloves. should be taken. Fluid intake should be relatively greater than average. Two main meals daily, separated by several hours, should be adopted.
- Health maintenance in the bilious temperament is supported by a Cold and Moist diet rich in fruit (e.g., pear, fig, watermelon, litchi, citrus) and vegetables (cucumber, lettuce), with less than usual heavy red meats. Water intake should be higher than average. Milk drinks are also fine, as are spices like coriander and cardamom.
- The person with a predominantly melancholic temperament should opt for a diet which is rich in Hot and Moist foods. Fruits like mangoes, peaches and bananas should be favoured, together with milk, cheese and honey, and meats like lamb, mutton and liver. Ginger is a beneficial herb to take regularly, and salt is fine.