Hundreds of millions of people are lactose intolerant, so why are we still recommending you to drink milk?

There is no need to say much about the benefits of drinking milk. Milk contains protein and is a high-quality source of calcium. A glass of milk every morning and evening can basically meet the calcium needs.

However, the ideal is beautiful, but the reality is a bit helpless - many people in our country are "lactose intolerant", and their stomachs will easily get upset after drinking milk.

Statistics show that lactose intolerance symptoms have a distinct geographical distribution, with an incidence of approximately 19% to 37% in Europe, 45% to 88% in Africa, and 54% to 74% in Asia [1]. my country belongs to the Asian region, and most people suffer from lactose intolerance.

Image source: https://unsplash.com/ Photographer: Anita Jankovic

The 2021 China Dairy Index Report shows that about 190 million residents in my country claim to have symptoms of lactose intolerance, of which 65.7% believe they cannot drink milk. In fact, there are more people with lactose intolerance than 190 million. After all, some people do not have the habit of drinking milk and do not know whether they are lactose intolerant.

In addition, Chunyu Doctor App once launched a "National Lactose Intolerance Survey", and the survey data showed that about 310 million people in China are lactose intolerant, and nearly 350 million are suspected lactose intolerant patients. In other words, there may be 660 million people in the country who cannot "get along" with lactose.

What is "lactose intolerance"? Do these people really not drink milk? Is there anything special that they need to pay attention to? Let's talk about it in detail today.

What exactly is lactose intolerance?

People with lactose intolerance will experience bloating, abdominal pain, and diarrhea after drinking milk. Sometimes after drinking milk, the stomach starts to growl after a while, and you may even have to rush to the toilet.

This is because milk contains about 5% lactose. After the lactose in milk enters our small intestine, it should normally be broken down by lactase in the small intestine into glucose and galactose that can be absorbed by the human body. However, some people lack lactase in their bodies and cannot completely break down the lactose. The unbroken lactose, as a substrate for intestinal bacteria, will be metabolized in the colon to produce fatty acids and gases, such as methane, carbon dioxide and hydrogen, which cause flatulence.

The large amount of intestinal gas produced by intestinal bacterial metabolism stimulates the intestinal nervous system through intestinal dilation, which can cause abdominal cramps, abdominal pain, and then diarrhea.

On the other hand, lactase activity gradually decreases with age, which can also lead to lactose intolerance.

What are the health risks of not drinking milk?

Milk is a major source of calcium in the diet, an important source of high-quality protein, and can also provide potassium and a small amount of B vitamins. If you don't drink milk or eat any dairy products, it will be difficult to meet the body's calcium needs through diet.

Generally, adults need to consume 800 mg of calcium per day, while children, adolescents, the elderly and special groups have higher calcium requirements.

Note: Recommended calcium intake for some groups of people

The calcium content of common milk on the market is mostly 100 mg/100 g. Drinking 300-500 g of milk every day can easily provide us with 300-500 mg of calcium. There are also some brands of milk with a higher calcium content, 50% more, up to 150 mg/100 g. If vitamin D is added to the ingredients, it can also better promote the absorption and utilization of calcium.

However, according to data from the "China Statistical Yearbook 2022" released by the National Bureau of Statistics, my country's per capita milk intake in 2021 was approximately 39.45 grams per day. Although it has increased, it is still less than 1/7 of the minimum recommended milk intake in the dietary guidelines, which is far from the recommended intake.

An example of a high calcium milk product

Insufficient intake of milk and dairy products increases the risk of calcium deficiency, which can seriously affect your health.

Osteoporosis: Calcium is the most abundant mineral in the human body. Long-term calcium deficiency can lead to decreased bone calcium content, brittle bones, osteoporosis, and increased risk of fractures. Don’t underestimate fractures. At the mildest, they can make you unable to take care of yourself, while at the worst, they can be fatal. Foreign literature reports that the mortality rate of hip fractures is as high as 33% one year after surgery, which is the main reason for the increased trauma-related mortality rate in the elderly. [3]

Statistics show that the probability of fractures doubles with every 10 years of age after the age of 50. [3] If you do not take calcium supplements when you are young, you will be more likely to suffer fractures in middle or old age.

Impact on development: Insufficient calcium intake in children and adolescents will affect bone development and cause growth retardation, which will not only affect bone density but also height.

Loose teeth: 99% of the human body's calcium is present in bones and teeth, so calcium deficiency will not only endanger bone health, but also affect the health of teeth, which can cause loose teeth and easy tooth decay.

Nerve and muscle excitation: Calcium deficiency can lead to hyperexcitability of muscles and nerves, causing muscle twitches, such as thigh cramps. Calcium deficiency can also cause insomnia and difficulty falling asleep.

Inducing cardiovascular disease: Calcium deficiency affects the contraction and relaxation of blood vessels, which may promote atherosclerosis and increase the risk of cardiovascular disease. In addition, drinking 300 ml of milk can ingest 540 mg of potassium, which can meet 27% of the daily potassium requirement. This is also helpful for controlling blood pressure. Insufficient potassium intake will also increase the risk of high blood pressure.

Can people who are lactose intolerant really not drink milk?

Let me give you the answer first: People who are lactose intolerant really don’t need to give up milk.

This is because most lactose intolerant patients can tolerate a certain amount of lactose. There is no need to completely refuse to drink milk. They can choose milk and dairy products that suit them according to their own needs.

Specifically, consider the following dairy products:

Lactose-free milk: Lactose-free milk does not contain lactose because the lactose has been processed in advance during the processing. For example, lactase is added during the processing to break it down into glucose and galactose. This prevents the complete lactose from entering the body and causing lactose intolerance.

Even people with severe lactose intolerance can drink it with confidence without any adverse reactions such as abdominal pain, bloating, diarrhea, etc. Some milk brands have launched low-lactose or zero-lactose products to benefit friends who are sensitive to lactose. We can choose based on factors such as calcium content.

An example of lactose-free milk

Moreover, after lactose is broken down into glucose and galactose, it tastes sweeter. This is because the sweetness of glucose is 4.6 times that of lactose, so the taste of zero lactose milk is mostly sweeter.

Yogurt: Yogurt is fermented from milk. The lactose in it is almost all broken down into lactic acid by lactic acid bacteria, leaving only a very small amount of lactose. Generally, people with lactose intolerance can accept it and will not experience discomfort after drinking it. According to the same amount of protein, 100 grams of fresh milk is equivalent to 100 grams of yogurt.

Cheese: Cheese is made by concentrating milk. Most of the lactose in the milk is lost in the whey, and the remaining lactose in the cheese curd is usually fermented into lactic acid by fermentation bacteria. Therefore, cheese contains almost no or only trace amounts of lactose and will not cause lactose intolerance. [4] Based on the same amount of protein, 100 grams of fresh milk is equivalent to 10 grams of cheese.

In addition, there are some tips you can try, such as avoiding drinking milk on an empty stomach and drinking milk in small amounts and multiple times.

In short, milk is an important way to supplement calcium in the diet. The calcium absorption rate of dairy products is the highest among natural foods, about 30%. [5] Milk is also convenient to consume. You can easily gulp down two large cups of it. It is a good calcium supplement without any burden and is worth recommending.

In addition, there are already many milks on the market that have reduced the effects of lactose. There is no need to give up drinking milk just because you are lactose intolerant.

References

[1] Storhaug, Christian Løvoldetal. "Country, regional, and global estimates for lactose malabsorption inadults: asystematic review and meta-analysis." Thelancet.Gastroenterology&hepatologyvol.2,10(2017):738-746.doi:10.1016/S2468-1253(17)30154-1

[2] Li Dongdan, Yan Jie, Yang Yanling. Lactose intolerance and dietary nutrition management[J]. Chinese Journal of Practical Pediatrics, 2022, 37(10): 758-763. DOI: 10.19538/j.ek2022100610.

[3] Yu Jian, Wang Ai, Li Yue, et al. Meta-analysis of risk factors for death within one year after surgery in elderly patients with hip fracture[J]. Chinese Journal of Bone and Joint Surgery, 2023, 12(06): 441-449.

[4] Qiu Junjie, Li Xiaozhong. Research on the current situation and countermeasures of China's cheese industry development[J]. Dairy and Human, 2022(06):4-13.

Author: Xue Qingxin, one of the first nutrition instructors of the National Health Commission, and a registered nutritionist in China