Is dietary supplement sourcant? Listen to BMJ?

original title: Is dietary supplement necessary? Listen to BMJ?Editor's Note:in recent years, the number of people taking dietary supplements, such as vitamin C, vitamin E, fish oil, and compound minerals, has increased in recent years. Some of these dietary supplements are said to be antioxidant, slow aging, and some can prevent osteoporosis.do these dietary supplements really work? Can they really prevent noncommunicable diseases? Does it work the same for everyone? Is it necessary for the general population to take these supplements?Today, we compiled a recent article in the journal BMJ on the health effects of vitamin and mineral supplements. It is hoped that this article can bring some inspiration and help to the relevant industry people and readers.Key message:randomized trial data do not support the risk of noncommunicable diseases in taking vitamins, minerals, and fish oil supplements.. People who take supplements are more likely than those who don't take supplements, who are more likely to be women, older, and tend to have higher levels of education, higher incomes, and healthier lifestyles.the use of supplements significantly reduced the prevalence of under-consumption of multiple nutrients, but also increased the rate of overconsumption of certain nutrients.requires further research (including low- and middle-income countries) to assess the long-term health effects of supplements on the general population and those with special nutritional needs.the popularity of dietary supplements vitamins and mineral supplements are the most commonly used dietary supplements. With the popularity of supplements, nutrients from dietary supplements have become an important part of total nutrient intake. However, these dietary supplements offer very different micronutrient content, some below the recommended intake, while others are much higher than the recommended intake.While supplements can be used to correct micronutrient deficiencies or maintain appropriate intake, over-the-counter supplements are usually purchased and taken by people withno-clinical symptoms, and the impact of vitamin and mineral supplements on "healthy" populations remains controversial.In this article, we collated and analyzed the effects of randomized studies of supplements to summarize the effects of dietary supplements on human health.Figure 1 Percentage of U.S. adults taking vitamins, minerals, and fish oil supplements.Source: National Health and Nutrition Survey 1999-2014Supplements?vitamin and mineral supplements have a huge global market, we will focus on North America and Europe because there is a lot of data on patterns of use and health outcomes in both regions. vitamin, mineral, and fish oil supplements are common among North American adults (Figure 1) . The use of certain types of nutrients is increasing day by day, such as from 1999 to 2012, the amount of vitamin D supplements used by U.S. adults (excluding intake from multiple vitamins and minerals) increased 4-fold, and the amount of omega-3 fatty acid supplements increased by 7 times. , while generally lower in other countries, supplement use is highly different compared to the United States and Canada (e.g. Denmark 51%, South Korea 34%, Australia 43%, UK 36%, Spain 6%, Greece 2%). This may be due to differences in the methods used to assess supplement utilization, resulting in differences in supplement utilization results in high-income countries. Survey data on supplement use among the general population at the national level remain sized in low- and middle-income countries. and in North America and Europe, there are significant differences in the use of supplements among different populations. In the United States, more than 70 percent of adults over the age of 65 take supplements, compared with about one-third of all children and adolescents. More women than men take supplements. also found a positive correlation between supplement use and educational and socio-economic status. At the same time, people who take supplements have healthier lifestyles, such as non-smoking, non-alcoholic, non-overweight, non-obese, and physical activity. important, people who take supplements tend to have a better overall diet than those who don't take supplements, and that most of the nutrients they take from their food have reached their recommended intake. Figure 2 The proportion of under-nutrition and overdose in U.S. adults Source: National Health and Nutrition Survey 1999-2014 BOX 1 Population Nutrient Definition: Average Needs (Estimated Average Requirement, EAR):
average daily nutritional intake that meets half of the health needs of the population. Undernutrition Intake:
prevalence of under-intake can be expressed as a percentage of the population whose nutrient intake is below average. tolerable maximum intake (Tolerable upper intake):
the highest level of daily intake that does not pose a hazard to almost all healthy individuals in a given population. The potential risk of health hazards increases when the intake exceeds the maximum limit that can be tolerated. Excess intake: the prevalence of
overtake can be expressed as a percentage of the population whose nutrient intake is higher than the highest tolerable intake. Is
supplement sane? at the population level, the use of supplements significantly increased the total intake of vitamins and minerals by 13. Among U.S. adults, vitamin B6, thiamine, and riboflavin are at least 5 times more likely to be taken from supplements, while vitamin B12 and vitamin E are taken from supplements 15 to 20 times 6 times from food. , the use of supplements has significantly reduced the proportion of people with inadequate nutrient intake in the general population (BOX 1), especially vitamins and minerals such as vitamin D and calcium, which are considered "deficiency" nutrients (Figure 2) 14. Despite the high use of supplements, under-micronutrient intake remains widespread in high-income countries, possibly because their dietary patterns are usually high-energy but nutrient-deficient. deficiencies in specific micronutrients (such as iodine, iron, zinc and vitamin A) are prevalent in low- and middle-income countries, and supplements are often recommended when dietary methods such as dietary adjustment, food fortification, or food supply do not improve under-absorption. (Editor's Note: Food fortification is a measure that points to the addition of nutrients to foods to enhance their nutritional value.) the United States and other countries use food-fortified methods, such as adding iodine to salt, vitamin D in milk, and adding vitamin B1 and B3 to refined flour, to help them eliminate conditions caused by associated nutrient deficiencies (goiter, rickets, foot disease, and brown skin disease, respectively) 16,17. widely used vitamin and mineral supplements in high-income countries can help increase nutrient intake in the population and may even lead to excess intake, exceeding the maximum limit of tolerable intake (BOX 1) 6. Although the total proportion of U.S. adults with a higher than the upper limit for most nutrients is less than 5% (Figure 2), some people may have far more nutrient intake than the upper limit. for example, in a national survey in Canada, more than 80 percent of children aged 1 to 3 taking dietary supplements had vitamin A and niacin intake exceeding the limit of 18. In the United States, 97 percent of young children taking supplements consume too much vitamin A and 68 percent consume more zinc. there is no high-quality evidence of the long-term adverse effects of excessive intake of some nutrients, so it is not clear whether this issue is of concern. Can
supplements prevent noncommunicable diseases? whether supplements can be effective in reducing the risk of noncommunicable diseases remains debatable. Contrary to the results of observational studies, evidence from randomized controlled trials suggests that supplements do not reduce the risk of cardiovascular disease, cancer or type 2 diabetes for healthy people without clinical nutritional deficiencies. Cardiovascular Disease 2013, a systematic review published by the U.S. Preventive Services Task Force (USPSTF) reviewed 15 randomized trials 20, showing the lack of benefits for cardiovascular events, especially in patients with risk factors. Although randomized trials of folic acid (either alone or in combination with vitamin B12 or B6) found a significant reduction in homocysteine levels in the plasma, the overall cardiovascular events did not decrease. While another systematic review has shown that supplementation can reduce the level of b vitamins of homocysteine, or reduce stroke risk 22, a large trial included in the meta-analysis has contributed significantly to this conclusion. in general, there is no consistent evidence to support the risk of cardiovascular risk by taking antioxidant supplements 22,24. "Vitamin D and Omega-3 Trials" (VITAL) is one of the few randomized trials to explore the use of supplements for primary prevention of cardiovascular disease. The trial found that vitamin D supplements (2000 IU/day) had no effect on the primary endpoint of cardiovascular disease (myocardial infarction, stroke, or cardiovascular death) in healthy people. previous large-scale trials, such as the Women's Health Initiative: Calcium and Vitamin D Supplement26 and Vitamin D Assessment Study 27, also showed that vitamin D supplements, whether taken alone or in combination with calcium, had no effect on cardiovascular risk. in the VITAL trial, supplementing omega-3 fatty acids (1 g/day) did not reduce the risk of major cardiovascular events in healthy people. However, supplementing omega-3 fatty acids may help improve some secondary endpoints, such as total myocardial infarction. this result is broadly consistent with the results of the meta-analysis, i.e. fish oil supplementation has no material effect on primary or secondary prevention of cardiovascular disease 29,30. , however, a meta-analysis report, including the latest trial, found that supplementing omega-3 fatty acids significantly reduced the risk of myocardial infarction. , therefore, whether the effect of fish oil supplementation on the risk of heart disease is greater than the risk of stroke, this requires further research. Cancer current evidence does not support the risk of cancer by vitamin and mineral supplements, and some evidence even suggests its potential harm. two randomized trials showed that beta-carotene supplementation may increase the risk of lung cancer in high-risk populations. a study on alpha-procopter, beta-carotene cancer prevention, reported that smokers who took beta-carotene at random had an 18% increased risk of lung cancer compared to smokers who did not take beta-carotene (20 mg/day). another trial on the efficacy of beta-carotene and retinol found that in smokers and workers exposed to occupational asbestos, the risk of lung cancer increased by 28% in both beta-carotene (30 mg/day) and retinol (vitamin A: 25,000 IU/day). a trial on selenium and vitamin E to prevent cancer found that men who took vitamin E (400 IU/day) supplements had a 17 percent increased risk of prostate cancer. Although folic acid supplementation in pregnant women has been shown to reduce the risk of neural tube defects in infants, there are concerns that high folic acid exposure may promote cancer progression, especially in countries where folic acid is given compulsory. most notably, taking a supplement to folic acid of up to 1 mg/day can promote the growth of undiagnosed large intestine adenomas 37. However, a meta-analysis analyzed 11 randomized trials and came to a different conclusion: folic acid supplementation neither increases nor reduces cancer risk in specific areas for the first five years. Despite evidence that vitamin D (taken alone or in conjunction with calcium) can reduce the total cancer mortality rate by 25,40, randomized trials did not find the benefits of vitamin D (taken alone or in conjunction with calcium) on cancer risk,