It has been eaten by humans throughout history, and is used as part of a meal, a snack, or as a component of sauces and desserts.
In addition, yogurt can contain beneficial bacteria and function as a probiotic. This can provide a variety of health benefits that go well beyond those of plain milk.
Most yogurt is a white, thick liquid, but many commercial brands have artificial colorants added to them.
The table below contains detailed information on the nutrients in yogurt (1).
Plain yogurt made from whole milk contains about 8.5 grams of protein in each cup (245 g).
The protein content of commercial yogurt is sometimes higher than in milk, because dry milk is sometimes added to yogurt during processing (2).
Proteins in yogurt can be divided into two families, whey and casein, depending on their solubility in water.
Water-soluble milk proteins are called whey proteins, whereas insoluble milk proteins are called caseins.
Both casein and whey are of excellent quality, rich in essential amino acids, and have a good digestibility.
The majority (80%) of proteins in yogurt are in the casein family, the most abundant of which is alpha-casein.
Whey is the smaller family of proteins found in milk products, accounting for 20% of the protein content in yogurt.
It is very high in branched-chain amino acids (BCAAs), such as valine, leucine and isoleucine.
Whey proteins have long been a popular supplement among bodybuilders and athletes.
Bottom Line: Yogurt is a great source of high-quality protein, including both casein (80%) and whey (20%).
The amount of fat in yogurt depends on the type of milk it is made from.
Yogurt can be produced from all kinds of milk, whole milk, low-fat milk or fat-free milk. The majority of yogurt sold in the US is either low-fat or fat-free (2).
The majority of fat in yogurt is saturated (70%), but it also contains a fair amount of monounsaturated fat.
Milk fat is unique with respect to the diversity of fatty acids it provides, containing as many as 400 different types of fatty acids (9).
Ruminant Trans Fats in Yogurt
Yogurt contains a family of trans fats called ruminant trans fats or dairy trans fats.
Unlike trans fats found in some processed food products, ruminant trans fats are considered to have beneficial health effects.
Bottom Line: The fat content of yogurt is variable, depending on the type. Most yogurts sold commercially are low-fat or fat-free.
Carbs in plain yogurt are mainly in the form of simple sugars called lactose (milk sugar) and galactose.
The lactose content of yogurt is lower than in milk.
This is because bacterial fermentation of yogurt results in lactose breakdown.
When lactose is broken down, it forms galactose and glucose. The glucose is mostly converted to lactic acid, the substance that adds the sour flavor to yogurt and other fermented milk products (15).
Most yogurts also contain considerable amounts of added sweeteners, usually sucrose (white sugar), along with various kinds of flavoring.
Bottom Line: Yogurt contains small amounts of natural milk sugar (lactose). Many brands are also high in added sugar.
Full-fat yogurt contains almost every single nutrient needed by humans.
However, there are various types of yogurt and their nutritional value may vary substantially.
For example, the nutritional value of yogurt may depend on the types of bacteria used in the fermentation process (17).
The following vitamins and minerals are found in particularly high amounts in conventional yogurt made from whole milk (1):
- Vitamin B12: A nutrient only found in foods of animal origin (18).
- Calcium: Milk products are excellent sources of calcium, in a form that is easily absorbed (19).
- Phosphorus: Yogurt is a good source of phosphorus, an essential mineral that plays an important role in biological processes.
- Riboflavin: Also called vitamin B2. Milk products are the main source of riboflavin in the modern diet (20).
Bottom Line: Yogurt is an excellent source of several vitamins and minerals, such as vitamin B12, calcium, phosphorus, and riboflavin.
Probiotics are live bacteria that have beneficial health effects when consumed.
These friendly bacteria are found in fermented milk products, such as yogurt with live and active cultures (21).
The main probiotics in fermented milk products are lactic acid bacteria and bifidobacteria (22).
Probiotics have many beneficial health effects, depending on the species and the amount taken.
- Enhanced immune system: Studies indicate that probiotic bacteria may promote enhanced immunity (23, 24, 25, 26, 27).
- Lower cholesterol: Regular intake of certain types of probiotics and fermented milk products may lower blood cholesterol (28, 29, 30, 31, 32).
- Vitamin synthesis: Bifidobacteria can synthesize or make available many kinds of vitamins, including thiamine, niacin, vitamin B6, vitamin B12, folate, and vitamin K (22).
- Digestive well-being: Fermented milk containing bifidobacterium may promote digestive well-being and lessen the symptoms of irritable bowel syndrome (33, 34).
- Protection against diarrhea: Probiotics may help treat diarrhea caused by antibiotics (35, 36, 37, 38, 39).
- Protection against constipation: Several studies suggest that regular consumption of yogurt, fermented with bifidobacterium, may reduce constipation (40, 41, 42).
- Improved lactose digestibility: Probiotic bacteria have been shown to improve the digestion of lactose, lessening the symptoms of lactose intolerance (43, 44).
These health benefits may not always apply to yogurt, mainly because some types of yogurt have been heat-treated (pasteurized) after the probiotic bacteria were added.
In heat-treated yogurts, the probiotic bacteria are dead and do not provide any health benefits.
For this reason, it is best to choose yogurt with active or live cultures.
Bottom Line: Yogurts with live or active cultures contain probiotic bacteria (probiotics) that may improve digestive health.
The health effects of milk and fermented dairy products, such as yogurt, have been widely studied.
Probiotic yogurt can provide numerous impressive health benefits that go well beyond that of non-fermented milk.
Probiotic yogurt has been associated with a variety of digestive health benefits.
Probiotics may also alleviate the symptoms of lactose intolerance by improving the digestion of lactose (44).
Bottom Line: Consumption of probiotic yogurt may improve gut health. It can reduce antibiotic-associated diarrhea, reduce symptoms of irritable bowel syndrome and help with the digestion of lactose.
Osteoporosis and Bone Health
Osteoporosis is a condition characterized by weak and brittle bones.
It is common among elderly people and is the main risk factor for bone fractures in this age group.
Dairy products have long been considered to be protective against osteoporosis.
Bottom Line: Yogurt is a rich source of calcium and protein, and may reduce the risk of osteoporosis.
Abnormally high blood pressure, also called hypertension, is one of the main risk factors for cardiovascular disease.
Studies suggest that regular consumption of yogurt may lower blood pressure in people with hypertension (46).
Bottom Line: Milk products, such as yogurt, may reduce the risk of abnormally high blood pressure (hypertension).
Yogurt may cause adverse effects in certain people, specifically those that are lactose intolerant or allergic to milk proteins.
Yogurt contains smaller amounts of milk sugar (lactose) than milk.
This is because some of the lactose in milk breaks down into glucose and galactose during yogurt production.
Therefore, it is better tolerated by people with lactose intolerance.
Bottom Line: Many people are intolerant to milk sugar (lactose) and need to avoid or limit their consumption of milk products.
Milk allergy is rare and more common among children than adults. It is triggered by milk proteins, whey and casein, found in all milk products (51).
Therefore, yogurt should be avoided by people with milk allergy.
It is important to keep in mind that many low-fat yogurts have a lot of sugar added to them.
For this reason, it is recommended that you read the label and avoid yogurts that have sugar (usually sucrose or high fructose corn syrup) on the ingredients list.
Bottom Line: Although regular yogurt is very healthy, many brands sold commercially have high amounts of added sugar, which can be very harmful when consumed in excess.
Yogurt is a food product made by fermenting milk.
Natural probiotic yogurt, with active or live cultures, is perhaps the healthiest of all dairy products, especially when it's free of added sugar.
It has various digestive health benefits, and may cut the risk of osteoporosis and reduce blood pressure.