Does eating red meat prevent dementia? Does eating chicken cause acid reflux? How to eat meat healthily

In cold seasons, people tend to eat more meat, especially beef and mutton, which make people feel warm.

The reason why eating meat makes people feel warm is, on the one hand, because the protein in it can promote the dissipation of body heat, and on the other hand, it may be because the iron in it is beneficial to prevent anemia, ensure normal biological oxidation, and allow the body to get sufficient energy supply.

In the long run, the protein, creatine, carnitine and various trace elements in meat are all beneficial to maintaining muscle mass, and muscle is the basis of exercise heat production.

Beef and mutton are both classic "red meats". They are high in protein and especially high in iron.

However, while happily eating meat, some people are also worried about:

Will eating too much meat affect your health?

I heard that red meat is a carcinogen? I heard that eating meat can promote dementia? Eating meat increases the risk of cardiovascular disease? Does eating meat promote diabetes?

This is a difficult question to answer. In the research on the relationship between food and health, the most inconsistent are eggs and meat.

Let’s first talk about the relationship between meat and dementia.

A consistent result among various studies is that eating processed meat products regularly increases the risk of dementia. The so-called processed meat products are sausages, ham, bacon, salted meat, and pickled meat.

What about fresh meat that has not been processed? The results are inconsistent. Some say that eating more fresh red meat can also promote dementia, while others say that eating red meat has nothing to do with dementia. Here are two recent research results published in 2021. Readers who are not interested in reading the research description, please turn to the end of the article for the summary and suggestions.

A study published in the American Journal of Clinical Nutrition is the result of an analysis of dietary data from 490,000 middle-aged and elderly people in the UK who were tracked for eight years (Zhang H, AJCN, 2021).

The analysis found that compared with people who ate processed meat less than once a week, those who ate processed meat five times a week (38g per day on average) had an 88% increased risk of dementia. Even if all possible influencing factors were eliminated (such as physical activity, body mass index, smoking status, sleep status, family history, health status, eating vegetables, fruits and fish, coffee and tea drinking habits, the amount of unprocessed meat eaten, etc.), it still increased by 67%. Compared with those who seldom ate, those who ate an average of 25g per day had a 43% increased risk.

However, compared with eating almost no unprocessed red meat, eating fresh red meat 2-3 times a week, an average of 44 grams per day, reduced the risk of Alzheimer's disease by 28%. The researchers calculated that 50 grams of red meat per day was associated with a 30% lower risk of Alzheimer's disease. The effect of poultry meat on reducing risk was not as obvious, but it was not found to increase risk either.

Overall, no increase in dementia risk was found for total meat consumption up to 96 grams per day (including red meat and poultry), but risk was slightly increased for a total of 113 grams per day.

This seemingly confusing research result may be a comprehensive reflection of multiple factors.

First, it is not unreasonable that an unreasonable vegetarian diet may increase the risk of dementia. This is because vegetarians who do not pay attention to nutritional supplements often lack vitamin B12, which is very important for the health of the nervous system. The body's storage capacity for vitamin B12 is very strong. After switching from a meat eater to a vegetarian, vitamin B12 deficiency often occurs only after several years.

At the same time, meat is an important source of high-quality protein. The neurotransmitters required for brain activity are made from protein amino acids. Previous studies have confirmed that insufficient protein intake increases the risk of dementia in the elderly.

Red meat is also a source of B vitamins and a variety of trace elements. Mental activity also requires a lot of oxygen and energy, and the smooth operation of energy metabolism requires the help of a variety of B vitamins and trace elements. Previous studies have found that iron deficiency anemia increases the risk of cognitive decline.

Meat is also a source of cholesterol. Brain cells contain very high levels of cholesterol, and as we age, the liver's ability to synthesize cholesterol decreases, so a moderate intake of protein foods containing cholesterol may be beneficial for the elderly.

I have said many times before that being a vegetarian is a technical job. For people who used to eat a lot of meat, a short-term vegetarian diet may have health benefits. However, being a vegetarian for many years is likely to bring about the risk of malnutrition, so it is best to do it under the guidance of a nutrition professional.

However, consuming a large amount of red meat will bring too much iron. Once too much iron is deposited in the brain, it will promote the occurrence of dementia. Too much iron will also increase the level of oxidative stress, which is not conducive to the prevention of dementia. Therefore, it is still necessary to eat meat in moderation.

When eating red meat, chicken and other foods, if you use cooking methods such as frying, smoking, or grilling over open flames, it will produce a lot of substances that promote inflammation, which is not conducive to preventing dementia.

Therefore, the benefits and harms of meat in preventing dementia are often intertwined. For each person and each family, the amount of meat eaten and the way it is cooked are different, and the combination with other foods, physical constitution and genetics are different, so the final health results are also different.

Why do processed meats have such a strong effect on promoting dementia risk?

On the one hand, compared with fresh red meat (lean meat), processed meat products have a higher fat content and too much saturated fat. Because processed products made from too lean meat do not taste good, products often need to be made with raw materials containing fat or minced fat.

On the other hand, processed meat products generally contain too much sodium. They contain a lot of sodium chloride (table salt), complex phosphate water retainers such as sodium tripolyphosphate, colorants such as sodium nitrite, and flavor enhancers such as sodium nucleotides and monosodium glutamate. Animal experiments have found that a high-salt diet can increase blood pressure, reduce blood flow to the brain, and cause a decrease in cognitive ability.

In addition, processed meat products also contain sodium nitrite and protein decomposition products combined with N-nitroso compounds, such as the more familiar nitrosamines. These substances will increase inflammation and increase oxidative stress levels, and these changes are all conducive to the occurrence of dementia.

The researchers did not explain why red meat (mainly beef in the UK) was most effective in preventing dementia, while poultry (mainly chicken in the UK) intake was not associated with dementia risk.

I personally think that an average daily intake of 50g of red meat is reasonable and is also within the recommended range of the Chinese Residents Dietary Guidelines. A small amount of red meat can not only improve the taste of the meal, but also help prevent anemia and protein deficiency, and increase the supply of trace elements. According to current research results, this amount will not increase the risk of chronic diseases.

Using the same data from this large-scale survey in the UK, another group of researchers analyzed the relationship between meat intake and the risk of 25 diseases (Papier K, BMC Med, 2021).

The researchers found that respondents who ate more meat were more likely to suffer from certain diseases:

- Eating just 20 grams of processed meat per day can increase the risk of diabetes, diverticular disease and colon polyps. This is not surprising, as previous results are similar.

——If the total amount of red meat and processed meat exceeds 70g, it may increase the risk of diseases such as ischemic heart disease, diabetes, diverticular disease and colorectal polyps.

- Each 30-gram increase in poultry consumption may be associated with an increased risk of gastroesophageal reflux disease, gastritis, duodenitis, diverticular disease, gallbladder disease, and diabetes. This finding is relatively new, as poultry consumption has not previously been associated with disease.

Researchers believe that this may be because people who consume more poultry tend to have higher body weight, and obesity increases the risk of gallbladder disease, diabetes and some gastrointestinal diseases.

Interestingly, the study found that increasing the intake of red meat reduces the risk of iron deficiency anemia. In other words, eating pork, beef and mutton is helpful in preventing anemia. However, switching to chicken is not the case, because the study found that people who eat more poultry not only do not reduce their risk of anemia, but even increase it...

I really don’t understand this result, and the researchers didn’t give an explanation. Although the heme iron content of chicken is not as high as that of lean pork, beef and mutton, it is not zero anyway. The bioavailability of heme iron is relatively high, and a little bit is better than nothing!

After all this discussion, many people may be confused. Should we eat meat? Should we eat red meat or white meat? How much meat should we eat?

Finally, let me sort it out for you

1 If you eat meat, pay attention to eating fresh meat first and eat less processed meat (sausage, ham, bacon, luncheon meat, etc.). These foods can only be eaten occasionally, such as during the Spring Festival. On average, the amount is very small when you eat 365 days a year.

2 If you don't have enough protein or need to gain muscle, it's right to eat meat every day. You can eat a little more during the muscle-building phase, but if you don't have such a large amount of exercise and muscle-building needs, you don't have to eat so much meat every day.

3 People who need to prevent cardiovascular disease, diabetes and gallbladder disease should pay attention to controlling the amount of fresh meat they eat to an average of 70 grams per day, eat less processed meat products, and choose low-fat cooking methods to avoid gaining weight.

4 People with anemia should give priority to red meat, especially beef, mutton and offal with high heme iron content, which will have a better iron supplement effect. The effect of chicken and duck meat is much worse.

5 For middle-aged and elderly people, it is not necessary to choose a vegetarian diet. Appropriate intake of meat, such as 50 grams of red meat per day, or eating red meat three days a week, may be more conducive to preventing dementia. But do not eat processed meat products frequently, which will promote the occurrence of dementia.

6 People with gastroesophageal reflux problems can control the amount of chicken they eat. Especially fried chicken, fried chicken wings, grilled chicken legs, etc., it may be better to eat less. In particular, do not eat chicken, grilled chicken wings, chicken burgers, etc. as midnight snacks, because people who are prone to gastric acid reflux should avoid eating within 3 hours before going to bed.

Finally, it should be noted that epidemiological data analysis can only find the correlation between some foods and diseases, but cannot explain the causal relationship. In other words, finding that people who eat more meat suffer more from a certain disease does not necessarily prove that the disease is caused by eating meat. There may be other potential factors at work. Different countries and regions have different eating habits and different races and constitutions, and their reactions to food will also vary. Therefore, there is no need to be too surprised by different research results.

The simplest way is

I believe in the summary analysis and risk assessment of multiple research results by mainstream nutrition experts. These works are carried out according to strict procedures and can sort out the most reliable suggestions from complex research results.

Ordinary people don't need to worry about it, just eat according to the Chinese Residents Dietary Guidelines. Wait for the new dietary guidelines to be released......

References:

1 Zhang H, et al. Meat consumption and risk of incident dementia: cohort study of 493,888 UK Biobank participants. American Journal of Clinical Nutrition, 2021, 114: 175-184

2 Papier K, et al. Meat consumption and risk of 25 common conditions: outcome-wide analyzes in 475,000 men and women in the UK Biobank study. BMC Medicine, 2021, 19:53

Source: Fan Zhihong_Original Nutrition Information