In nutrition, diet is the sum of food consumed by a person or other organism. [1] 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, essential amino acids from protein and essential fatty acids from fat-containing food, also food energy in the form of carbohydrate, protein, and fat. Dietary habits and choices play a significant role in the quality of life, health and longevity.
A healthy diet can improve and maintain health, which can include aspects of mental and physical health. [2] Specific diets, such as the DASH diet, can be used in treatment and management of chronic conditions. [2]
Dietary recommendations exist for many different countries, and they usually emphasise a balanced diet which is culturally appropriate. These recommendation are different from dietary reference values which provide information about the prevention of nutrient deficiencies.
Exclusionary diets are diets with certain groups or specific types of food avoided, either due to health considerations or by choice. [2] Many do not eat food from animal sources to varying degrees (e.g. flexitarianism, pescetarianism, vegetarianism, and veganism) for health reasons, issues surrounding morality, or to reduce their personal impact on the environment [3] (e.g. environmental vegetarianism). People on a balanced vegetarian or vegan diet can obtain adequate nutrition, but may need to specifically focus on consuming specific nutrients, such as protein, iron, calcium, zinc, and vitamin B12. [4] [2] [5] Raw foodism and intuitive eating are other approaches to dietary choices. Education, income, local availability, and mental health are all major factors for dietary choices. [2]
A particular diet may be chosen to promote weight loss or weight gain. Changing a person's dietary intake, or "going on a diet", can change the energy balance, and increase or decrease the amount of fat stored by the body. [2] The terms "healthy diet" and "diet for weight management" (dieting) are often related, as the two promote healthy weight management. [6] [7] If a person is overweight or obese, changing to a diet and lifestyle that allows them to burn more calories than they consume may improve their overall health, [2] possibly preventing diseases that are attributed in part to weight, including heart disease and diabetes. [8] Within the past 10 years, obesity rates have increased by almost 10%. [9] Conversely, if a person is underweight due to illness or malnutrition, they may change their diet to promote weight gain. Intentional changes in weight, though often beneficial, can be potentially harmful to the body if they occur too rapidly. Unintentional rapid weight change can be caused by the body's reaction to some medications, or may be a sign of major medical problems including thyroid issues and cancer among other diseases. [10]
An eating disorder is a mental disorder that interferes with normal food consumption. It is defined by abnormal eating habits, and thoughts about food that may involve eating much more or much less than needed. [11] Common eating disorders include anorexia nervosa, bulimia nervosa, and binge-eating disorder. [12] Eating disorders affect people of every gender, age, socioeconomic status, and body size. [12]
Agriculture is a driver of environmental degradation, such as biodiversity loss, climate change, desertification, soil degradation and pollution. The food system as a whole – including refrigeration, food processing, packaging, and transport – accounts for around one-quarter of greenhouse gas emissions. [13] More sustainable dietary choices can be made to reduce the impact of the food system on the environment. These choices may involve reducing consumption of meat and dairy products and instead eating more plant-based foods, and eating foods grown through sustainable farming practices. [14]
Some cultures and religions have restrictions concerning what foods are acceptable in their diet. For example, only Kosher foods are permitted in Judaism, and Halal foods in Islam. Although Buddhists are generally vegetarians, the practice varies and meat-eating may be permitted depending on the sects. [15] In Hinduism, vegetarianism is the ideal. Jains are strictly vegetarian and in addition to that the consumption of any roots (ex: potatoes, carrots) is not permitted.
In Christianity there is no restriction on the kinds of animals that can be eaten, [16] [17] though various groups within Christianity have practiced specific dietary restrictions for various reasons. [18] The most common diets used by Christians are Mediterranean and vegetarianism. [19] [20] [21] [22]
Food type | Omnivorous | Carnivorous | Pescetarian | Pollotarian | Semi-vegetarian | Vegetarian | Vegan | Fruitarian | Paleo | Ketogenic | Jewish | Islamic | Hindu | Jain |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Alcoholic drinks | Yes | No | Yes | Yes | Yes | Yes | Yes | No | No | Maybe | Maybe | No | Maybe | No |
Fruit | Yes | No | Yes | Yes | Yes | Yes | Yes | Yes | Yes | No | Yes | Yes | Yes | Maybe |
Berries | Yes | No | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Maybe | Yes | Yes | Yes | Yes |
Vegetables | Yes | No | Yes | Yes | Yes | Yes | Yes | No [lower-alpha 1] | Yes | Yes | Yes | Yes | Yes | Yes |
Greens | Yes | No | Yes | Yes | Yes | Yes | Yes | No | Yes | Yes | Yes | Yes | Yes | Maybe |
Legumes | Yes | No | Yes | Yes | Yes | Yes | Yes | Maybe | No | No | Yes | Yes | Yes | Yes |
Nuts | Yes | No | Yes | Yes | Yes | Yes | Yes | Maybe | Yes | Maybe | Yes | Yes | Yes | Maybe |
Tubers | Yes | No | Yes | Yes | Yes | Yes | Yes | No | Maybe [lower-alpha 2] | No | Yes | Yes | Yes | Maybe |
Grains | Yes | No | Yes | Yes | Yes | Yes | Yes | Maybe | No | No | Yes | Yes | Yes | Yes |
Honey | Yes | No | Yes | Yes | Yes | Yes | No | No | Yes | No | Yes | Yes | Yes | No |
Dairy | Yes | Maybe [lower-alpha 3] | Maybe | Maybe | Maybe | Maybe [lower-alpha 4] | No | No | No | Maybe | Yes [lower-alpha 5] | Yes | Yes | Yes |
Eggs | Yes | Yes | Maybe | Yes | Maybe | Maybe [lower-alpha 6] | No | No | Yes | Yes | Yes | Yes | Maybe | No |
Insects | Yes | Yes | No | No | Sometimes | No | No | No | Yes | Yes | No [lower-alpha 7] | No [lower-alpha 7] | Maybe | No |
Shellfish | Yes | Yes | Yes | No | Sometimes | No | No | No | Yes | Yes | No | Maybe [lower-alpha 8] | Maybe | No |
Fish | Yes | Yes | Yes | No | Sometimes | No | No | No | Yes | Yes | Yes | Yes | Maybe | No |
Poultry | Yes | Yes | No | Yes | Sometimes | No | No | No | Yes | Yes | Yes | Yes | Maybe | No |
Mutton | Yes | Yes | No | No | Sometimes | No | No | No | Yes | Yes | Yes | Yes | Maybe | No |
Venison | Yes | Yes | No | No | Sometimes | No | No | No | Yes | Yes | Yes | Yes | Maybe | No |
Pork | Yes | Yes | No | No | Sometimes | No | No | No | Yes | Yes | No | No | Maybe | No |
Beef | Yes | Yes | No | No | Sometimes | No | No | No | Yes | Yes | Yes | Yes | Maybe | No |
Dieting is the practice of eating food in a regulated way to decrease, maintain, or increase body weight, or to prevent and treat diseases such as diabetes and obesity. As weight loss depends on calorie intake, different kinds of calorie-reduced diets, such as those emphasising particular macronutrients, have been shown to be no more effective than one another. As weight regain is common, diet success is best predicted by long-term adherence. Regardless, the outcome of a diet can vary widely depending on the individual.
Vegetarianism is the practice of abstaining from the consumption of meat. It may also include abstaining from eating all by-products of animal slaughter. A person who practices vegetarianism is known as a vegetarian.
Vegetarian cuisine is based on food that meets vegetarian standards by not including meat and animal tissue products.
A food pyramid is a representation of the optimal number of servings to be eaten each day from each of the basic food groups. The first pyramid was published in Sweden in 1974. The 1992 pyramid introduced by the United States Department of Agriculture (USDA) was called the "Food Guide Pyramid" or "Eating Right Pyramid". It was updated in 2005 to "MyPyramid", and then it was replaced by "MyPlate" in 2011.
The Mediterranean diet is a diet inspired by the eating habits and traditional food typical of southern Spain, southern Italy, and Crete, and formulated in the early 1960s. It is distinct from Mediterranean cuisine, which covers the actual cuisines of the Mediterranean countries, and from the Atlantic diet of northwestern Spain and Portugal. While inspired by a specific time and place, the "Mediterranean diet" was later refined based on the results of multiple scientific studies.
A lacto-vegetarian diet is a diet that abstains from the consumption of meat as well as eggs, while still consuming dairy products such as milk, cheese, yogurt, butter, ghee, cream, and kefir.
A plant-based diet is a diet consisting mostly or entirely of plant-based foods. Plant-based diets encompass a wide range of dietary patterns that contain low amounts of animal products and high amounts of fiber-rich plant products such as vegetables, fruits, whole grains, legumes, nuts and seeds. They do not need to be vegan or vegetarian, but are defined in terms of low frequency of animal food consumption.
Vegetarian nutrition is the set of health-related challenges and advantages of vegetarian diets.
A healthy diet is a diet that maintains or improves overall health. A healthy diet provides the body with essential nutrition: fluid, macronutrients such as protein, micronutrients such as vitamins, and adequate fibre and food energy.
Ovo vegetarianism is a type of vegetarianism which allows for the consumption of eggs but not dairy products, in contrast with lacto vegetarianism. Those who practice ovo vegetarianism are called ovo-vegetarians. "Ovo" comes from the Latin word for egg.
Vegetarian and vegan dietary practices vary among countries. Differences include food standards, laws, and general cultural attitudes toward vegetarian diets.
Vegetarian Diet Pyramid is a nutrition guide that represents a traditional healthy vegetarian diet. Variations of this traditional healthy vegetarian diet exist throughout the world, particularly in parts of North America, Europe, South America and, most notably, Asia. Given these carefully defined parameters, the phrase "Traditional Vegetarian Diet" is used here to represent the healthy traditional ovo-lacto vegetarian diets of these regions and peoples. A pyramid was created by Oldways Preservation Trust in 1998 with scientific research from Cornell and Harvard University and specific reference to the healthy patterns of eating demonstrated by the Mediterranean Diet Pyramid.
Weight management refers to behaviors, techniques, and physiological processes that contribute to a person's ability to attain and maintain a healthy weight. Most weight management techniques encompass long-term lifestyle strategies that promote healthy eating and daily physical activity. Moreover, weight management involves developing meaningful ways to track weight over time and to identify the ideal body weights for different individuals.
Lacto-ovo vegetarianism or ovo-lacto vegetarianism is a type of vegetarianism which forbids animal flesh but allows the consumption of animal products such as dairy and eggs. Unlike pescetarianism, it does not include fish or other seafood. A typical ovo-lacto vegetarian diet may include fruits, vegetables, grains, legumes, meat substitutes, nuts, seeds, soy, cheese, milk, yogurt and eggs.
Pescetarianism is a dietary practice in which seafood is the only source of meat in an otherwise vegetarian diet. The inclusion of other animal products, such as eggs and dairy, is optional. According to research conducted from 2017 to 2018, approximately 3% of adults worldwide are pescetarian.
Vegan nutrition refers to the nutritional and human health aspects of vegan diets. A well-planned vegan diet is suitable to meet all recommendations for nutrients in every stage of human life. Vegan diets tend to be higher in dietary fiber, magnesium, folic acid, vitamin C, vitamin E, and phytochemicals; and lower in calories, saturated fat, iron, cholesterol, long-chain omega-3 fatty acids, vitamin D, calcium, zinc, and vitamin B12.
Nutrition psychology (NP) is the psychological study of the relationship between dietary intake and different aspects of psychological health. It is an applied field that uses an interdisciplinary approach to examine the influence of diet on mental health. Nutrition psychology seeks to understand the relationship between nutritional behavior and mental health/well-being NP is a sub-field of psychology and more specifically of health psychology. It may be applied to numerous different fields including: psychology, dietetics, nutrition, and marketing. NP is a fairly new field with a brief history that has already started to contribute information and knowledge to psychology. There are two main areas of controversy within nutrition psychology. The first area of controversy is that the topic can be viewed in two different ways. It can be viewed as nutrition affecting psychological functions, or psychological choices and behavior influencing nutrition and health. The second controversy is the defining of what is "healthy" or "normal" as related to nutrition.
Megan Rossi is a dietitian, nutritionist and author specialising in the microbiome. Her PhD in gut health received the Dean's Award top 5% for Outstanding Research Higher Degree.
Suzanne Marie Babich, formerly Suzanne Havala Hobbs is an American public health scientist, food writer, registered dietitian and vegetarianism activist. She was the primary author for the American Dietetic Association's 1988 and 1993 vegetarian position papers.