New healthy trend: Adults add some milk every day

With the rapid development of my country's economy and the change of lifestyle, national nutrition and health have received widespread attention from the whole society. Milk and dairy products are rich in nutrition, and drinking milk every day has a positive effect on our health.

There is a certain gap between the current dairy intake level of Chinese residents and that of developed countries. The national guidelines also suggest that appropriate dairy intake is of great significance to further improving the nutritional and health status of Chinese residents.

my country's traditional dietary pattern has distinct characteristics

However, the proportion of dairy intake is relatively low

A reasonable diet is the foundation of health. The traditional dietary structure of Chinese residents is mainly plant-based foods, supplemented by animal-based foods. The food types are diverse, and the proportion of plant-based foods such as cereals, fruits and vegetables, and soybeans is relatively high, which has distinct characteristics. With economic development and improved living standards, the consumption of animal foods has increased, but the proportion of dairy products is still low, and the problem of unreasonable dietary structure remains serious. Among them, milk intake is far below the recommended level .

Dairy products are rich in nutrients. Every 300 mL of milk provides 15%, 30%, 39% and 27% of the recommended amount of protein, vitamin B2, calcium and potassium for adults, respectively . Therefore, dairy products, as a high-nutrient-density food and an important part of a balanced diet, are recommended by various recognized healthy dietary patterns, such as the Mediterranean dietary pattern, the DASH dietary pattern, the Japanese dietary pattern, etc. They also occupy an important position in the dietary guidelines of countries around the world.

The Dietary Guidelines for Chinese Residents (2022) recommends "consuming a variety of dairy products regularly, with an intake equivalent to more than 300 mL of liquid milk per day." The dietary guidelines for pregnant women and nursing mothers, the elderly, and lacto-ovo vegetarians all recommend dairy intake. For details, see the guidelines.

The nutritional and health benefits of dairy products have been fully proven

Moderate intake of dairy products is good for health of adults

Dairy products have outstanding nutritional value and are of great significance for maintaining and improving physical health. Studies based on the Chinese population show that dairy intake can significantly reduce the risk of all-cause mortality . This is related to the fact that dairy products can effectively promote overall nutritional levels, ensure bone and muscle health, enhance the body's immunity, prevent chronic non-communicable diseases, and maintain good sleep and healthy emotions .

Dairy products are considered an important food for preventing and correcting malnutrition. In people at risk of malnutrition, such as the elderly, the intake of dairy products can safeguard the body's nutritional status and prevent the occurrence of complications associated with malnutrition.

Dairy products are essential for maintaining healthy bones and skeletal muscles. The protein, calcium, phosphorus, magnesium and vitamin D in dairy products are all important nutrients for maintaining bone health.

Studies have shown that dairy products or adding milk calcium to food can effectively increase the bone mass of young people and reduce bone loss in the elderly . Specific functional ingredients in dairy products, such as α-lactalbumin, lactoferrin, probiotics, and prebiotics , play an important regulatory role in key aspects of bone metabolism, such as the proliferation and differentiation of osteoblasts.

In people with low dietary calcium intake or dairy product intake, moderate dairy product intake has a positive effect on bone health. The overall calcium and dairy product intake of the Chinese population is at a low level. Prospective studies based on the Chinese population have confirmed that moderate dairy product intake can significantly reduce the risk of fractures .

In addition, dairy products are beneficial to muscle health. Milk protein can increase the lean body mass of young fitness people, improve skeletal muscle strength and power, explosive power and endurance, improve exercise performance, and promote recovery after exercise.

For the elderly, dairy product supplementation can significantly increase the volume of limb muscles, prevent muscle loss caused by aging , and ensure their motor function.

Dairy products can promote the improvement of the body's immune function. They can correct nutritional deficiencies and maintain and protect the body's normal immune function. At the same time, dairy products are rich in immune active substances, such as lactoferrin, casein, whey protein, immunoglobulin, etc., which can promote the body's immune balance by inhibiting the release of inflammatory factors and reducing oxidative stress reactions. This effect is more significant in people with metabolic disorders.

At present, whey protein has been included in the catalog of health food ingredients in my country. Daily intake of 6 to 25 g has the effect of enhancing immunity.

In addition, probiotics and their metabolites used in the production of fermented dairy products can enhance the body's overall immunity by directly hindering the binding of pathogens to the host, or by regulating the intestinal flora and improving the intestinal microecology. Many studies have shown that fermented milk can effectively reduce the infection ability of various pathogens such as rabies virus, herpes simplex virus, Zika virus, hepatitis virus, etc., and help reduce the risk of infectious diseases. During the new coronavirus epidemic, studies in different countries have suggested that higher dairy product intake is associated with lower COVID-19 infection rates. In addition, a number of randomized controlled trials have shown that fermented milk can improve the immune effect of vaccines in the elderly .

Appropriate intake of dairy products is of great significance for the prevention and control of chronic non-communicable diseases. In the early days, fat, especially saturated fatty acids, in milk were considered to increase the risk of chronic diseases.

However, existing studies have shown that dairy fat may have a positive effect on metabolic regulation . Large cohort studies have shown that when blood levels of C15∶0, C17∶0 and trans-C16∶1 (n-7) fatty acids (mainly from milk) are high, the risk of diabetes is lower. Conjugated linoleic acid, which is rich in milk, has been shown to improve insulin sensitivity and reduce the risk of insulin resistance.

In addition, specific functional ingredients contained in dairy products can also help prevent and control chronic diseases. For example, calcium in dairy products can promote fat oxidation and decomposition, reduce fat absorption in the small intestine and promote bowel movements.

Fermented dairy products such as yogurt can regulate energy and inflammation-related pathways by regulating intestinal flora, increasing the abundance of intestinal probiotics, and promoting the release of short-chain fatty acids.

The tripeptide in milk can inhibit angiotensin converting enzyme, promote the production of vasodilators, regulate sympathetic nerve activity, and thus play a role in lowering blood pressure.

Glycomacropeptide in milk has anti-inflammatory effects and can prevent the occurrence of gout. Many prospective studies and systematic reviews, including those on the Chinese population, have shown that dairy product intake can effectively reduce overweight and obesity, improve body composition, prevent diabetes, and reduce cardiovascular disease.

In response to this, the Chinese Nutrition Society proposed during the 2024 National Nutrition Week: milk beans add nutrition, less oil is healthier. The ten core messages of adding milk are as follows:

Milk and dairy products have so many benefits, so don’t forget to drink milk every day.

References

1. Food Nutrition and Health Branch of Chinese Institute of Food Science and Technology. Expert consensus on dairy products and adult nutrition and health[J]. Journal of Chinese Institute of Food Science and Technology, 2023, 23(10): 444-451.

2. Chinese Nutrition Society