Zinc is an important trace element. It plays a variety of indispensable roles in the human body and is widely involved in protein, lipid, nucleic acid metabolism, and gene transcription processes. Do you know what is zinc’s benefits and side effects?
Due to the importance of zinc to men’s health (considered as a nutrient related to aphrodisiac), if lack of it will seriously affect fertility, it is also called sex minerals
Table of Contents
- What is zinc?
- What happens to zinc deficiency? What are the symptoms?
- What are the ethnic groups prone to zinc deficiency?
- What are the benefits of zinc supplementation?
- 1. Zinc benefits blood sugar control
- 2. Zinc benefits blood pressure regulation
- 3. Zinc beneficially regulates body weight
- 4. Zinc benefits male infertility
- 5. Can zinc improve measles?
- 6. Zinc strengthens immunity and accelerates cold recovery
- 7. Zinc reduces the risk of cancer in the digestive tract
- 8. Zinc reduces sore throat after surgery
- 9. Zinc can improve blood lipids
- 10. Zinc benefits Parkinson’s disease
- 11. Zinc improves tinnitus symptoms
- 12. Zinc improves acne
- 13. Zinc prevents prostate cancer
- What are the side effects of zinc?
- Safety precautions
- Food sources of zinc and recommended dosage
- Where to buy the most recommended zinc supplement?
What is zinc?
Zinc is the second-largest metabolic micronutrient after iron in the human body. It is an important catalyst (related to more than 100 enzymes), structure, and regulating ions. It participates in homeostasis, immune response, cell signaling, oxidative stress, Physiological processes such as apoptosis and aging.
Zinc is involved in DNA synthesis, RNA transcription, cell division and activation, and prevention of apoptosis. In addition to the nuances of molecular function, it is also necessary for sperm production, embryonic and fetal growth.
Human tissue contains about 2 to 3 grams of zinc, and nearly 90% is found in muscles and bones. Other organs containing high concentrations of zinc include the prostate, liver, gastrointestinal tract, kidney, skin, lung, brain, heart, and pancreas
What happens to zinc deficiency? What are the symptoms?
Symptoms of zinc deficiency are non-specific, including growth retardation, rash, unexplained weight loss, diarrhea, hair loss, glossitis, nail dystrophy, decreased sense of smell and taste, decreased immunity, difficulty in healing wounds, loss of appetite, mood disorders, Dry skin, hypogonadism (erectile dysfunction) in men.
The overall incidence of zinc deficiency worldwide is expected to exceed 20%. In developing countries, it may affect more than 2 billion people.
This widespread occurrence, along with the diversity of clinical manifestations, makes zinc deficiency a serious nutritional problem with a great impact on human health.
The blood test of zinc is usually inaccurate because most zinc is accumulated in the cells and is not free in the blood.
What are the ethnic groups prone to zinc deficiency?
- Suffering from inflammatory gastrointestinal diseases
- Alcoholics
- Pregnant women and lactating women
- Vegetarian
- Suffering from chronic kidney disease
- Malnutrition, including anorexia or bulimia
- Sickle cell anemia
- Genetic variation
What are the benefits of zinc supplementation?
1. Zinc benefits blood sugar control
Diabetes is a group of chronic metabolic diseases characterized by increased blood glucose levels due to the body’s inability to produce insulin or resistance to insulin action, or both.
Due to population growth, aging, urbanization, unhealthy eating habits, obesity and lack of physical exercise, the prevalence of diabetes and pre-diabetes is rising globally.
A systematic literature review and meta-analysis (including 32 randomized placebo-controlled trials with a total of 1700 participants in diabetes and high-risk group) pointed out that zinc supplementation subjects had fasting blood glucose and 2 hours after a meal There were statistically significant reductions in blood glucose, fasting insulin, steady-state model assessment of insulin resistance, glycated hemoglobin, and high-sensitivity c-reactive protein concentrations.
In addition, subgroup analyses show that the effects of lowering fasting blood glucose are most pronounced in patients with diabetes and those using inorganic zinc supplements.
The underlying mechanism is related to zinc can improve the interaction between insulin receptors, increase the processing rate of glucose, and improve glucose tolerance.
*Conclusion: Zinc supplementation is positive for diabetes prevention or adjuvant therapy (especially for diabetic patients), but more large-scale studies are still needed to support it.
2. Zinc benefits blood pressure regulation
Hypertension is the main risk factor for cardiovascular events and death. Clinically, 69% of the first myocardial infarction, 77% of the first stroke, 74% of heart failure, and 60% of peripheral arterial diseases are related to hypertension.
The diagnosis of hypertension is mainly systolic blood pressure of 140 mm Hg or higher, or diastolic blood pressure of 90 mm Hg or higher, affecting about 29% of American adults, and 22% of hypertensive patients do not know that they have the disease.
A systematic literature review and meta-analysis (including 9 randomized controlled clinical trials with 544 participants) pointed out that zinc supplementation can significantly reduce systolic blood pressure, but has no significant effect on diastolic blood pressure.
In addition, the supplemental dose and time and blood pressure changes were not found to be non-linearly related.
The underlying mechanism is related to zinc contributing to the activity of nitric oxide synthase, enhancing the activity of peroxide removal, and producing angiotensin-converting enzyme and neutral endopeptidase.
*Conclusion: Zinc supplementation may be helpful for blood pressure regulation, but the relevant results still need to be further verified by more large-scale high-quality tests.
3. Zinc beneficially regulates body weight
Due to the interaction between biological characteristics, behavior, and fattening environment, long-term weight management is extremely challenging.
Obesity is an important health problem because it is easy to cause people to suffer from a variety of comorbidities, including high blood pressure, dyslipidemia, coronary heart disease, type 2 diabetes, stroke, cancer, and osteoarthritis, shorten life and reduce life quality.
A meta-analysis of literature (including 28 observational studies) pointed out that serum zinc levels in children and adult obese patients were significantly lower.
Another meta-analysis of literature (including 27 randomized controlled trials with a total of 1438 participants) pointed out that in the overall analysis, zinc supplementation had no significant effect on any weight-related results.
However, subgroup analysis showed that zinc supplementation increased the weight of hemodialysis patients and reduced the weight of individuals who are overweight/obese but otherwise healthy.
*Conclusion: Zinc deficiency is related to obesity, and for specific ethnic groups, supplementation of zinc may have the effect of regulating body weight.
4. Zinc benefits male infertility
Infertility is a common clinical problem. 13% to 15% of couples worldwide are affected by infertility, and about 50% of the causes can be attributed to malefactors.
Male factor infertility is characterized by abnormal semen analysis, such as low or missing sperm count, low sperm motility, and the use of any drugs, tobacco, alcohol, or illegal drugs.
After 40 years of age, DNA damage in male sperm will increase significantly, and sperm motility and viability will also decrease.
A systematic literature review and meta-analysis (including 20 studies involving 2600 infertile men and 867 normal controls) pointed out that the zinc content in infertile men’s seminal plasma was significantly lower than that of normal men. The additional zinc supplementation can significantly increase semen volume, sperm motility, and normal sperm morphology percentage in infertile men.
*Conclusion: Zinc supplementation may have a positive effect on male fertility, but it is limited to small sample size and more research is needed to corroborate it.
5. Can zinc improve measles?
Measles is infections of the respiratory system, immune system, and skin caused by the measles virus. They are highly contagious and vaccine-preventable diseases.
Despite the existence of safe and effective vaccines, measles is still the main cause of global morbidity and mortality, especially in young children, and related complications include pneumonia and encephalitis.
The disease is characterized by the appearance of high fever (usually >40°C), Coriolis spots (spots in the mouth, usually appearing 2-3 days before the rash, lasting 3-5 days), discomfort, loss of appetite, red eyes, Runny nose, lethargy, symptoms usually appear 7 to 14 days after exposure to the virus.
A Cochrane Database of Systematic Reviews (including a double-blind randomized controlled trial) pointed out that compared with placebo, oral zinc is necessary to solve the fever and shortness of breath, the time required for appetite recovery, and achieve ” The status of “significantly improved” or “cured” does not significantly help.
*Conclusion: Because of the low quality of the existing evidence, there is insufficient evidence to confirm or refute the effects of zinc supplementation on measles in children.
6. Zinc strengthens immunity and accelerates cold recovery
Cold is the most common self-limiting viral infection in the world. The main symptoms are sneezing stuffy nose, sore throat, cough, hoarse voice, headache, fever and muscle pain.
Most of the existing cold treatment methods are mainly to relieve symptoms, but there is no substantial help to fight the cold killer-the virus.
It is clinically found that zinc is very important for the healthy development of immune cells. If zinc is lacking, it will easily cause abnormal immune function and prone to infection. The potential anti-cold mechanism of zinc (listed below).
- Increase the production of antiviral interferon
- Prevent viruses from attaching to the respiratory tract
- Antiviral proliferation
- Inhibits the release of histamine and inflammatory hormones
A literature meta-analysis (including 3 randomized double-blind trials with a total of 199 participants) pointed out that compared to placebo, the use of zinc lozenges (dose between 80-92 mg per day) in addition to helping The recovery rate of cold is 3.1 times, and the cure rate is also 2.6 times higher (especially within 24 hours of cold symptoms).
*Conclusion: Taking zinc lozenges at the beginning of a cold may speed up recovery, but the best dosage form and frequency of use still need more research to confirm.
7. Zinc reduces the risk of cancer in the digestive tract
The gastrointestinal tract is a term used to define a series of tubular structures and accessory organs. They are involved in the process of digesting and absorbing food and excluding residual waste.
Any part of the gastrointestinal tract may be affected by malignant tumors, with the highest incidence being the esophagus, stomach, and colon.
A literature review and meta-analysis (including 19 studies with approximately 400,000 participants) pointed out that compared with the group with the least zinc intake, the subjects with the highest intake can reduce the risk of gastrointestinal cancer by 18%. In particular, colorectal cancer is the most significant.
Subgroup analysis also found that zinc intake was significantly associated with esophageal and gastric cancer risk in Asia, but no association was found in the United States and Europe.
*Conclusion: The intake of zinc is inversely related to the risk of digestive tract cancer, especially colorectal cancer.
8. Zinc reduces sore throat after surgery
Postoperative sore throat is mainly caused by tracheal intubation during surgery. It is one of the most common postoperative adverse reactions complained by patients. The incidence rate is about 30% to 70%. The cause is often related to age, gender, smoking, and operation. The technique, diameter, duration, catheter design, and intraoperative tube movement.
A randomized, double-blind, placebo-controlled study (targeting 79 patients undergoing endotracheal intubation surgery) pointed out that oral zinc tablets (40 mg 30 minutes before surgery) can reduce the incidence and severity of postoperative throat pain.
*Conclusion: Preoperative oral zinc ingots can reduce the pain caused by surgical laryngeal intubation, but it is limited by the small number of samples, which needs to be verified by more large-scale experiments.
9. Zinc can improve blood lipids
Dyslipidemia is currently recognized as a risk factor for atherosclerosis. It is prone to cause coronary artery disease, cerebrovascular disease, and peripheral vascular disease in the long run.
Studies have shown that every 40 mg/dl decrease in LDL cholesterol (LDL-c) can reduce major adverse cardiovascular events by 24%.
A systematic literature review and meta-analysis (including 32 studies with a total of 14,515 participants) pointed out that zinc supplementation can help reduce a variety of blood lipid values, including total cholesterol, low-density lipoprotein cholesterol, and triglycerides Among them, the improvement of the non-healthy population (obesity, type 2 diabetes, end-stage renal failure, and hemodialysis) is the most significant.
The underlying mechanism is related to zinc’s ability to improve insulin secretion or reduce insulin resistance, which in turn affects lipid metabolism.
*Conclusion: Zinc supplementation has the function of regulating blood lipids, especially for patients with metabolic syndrome.
10. Zinc benefits Parkinson’s disease
Parkinson’s disease is a neurodegenerative disease related to aging. It is estimated that the incidence of about 1% of the global population over 60 years old, the most obvious feature is movement tremor, stiffness, delay, and posture Stable, etc.
Although the main pathogenic mechanism is unknown, inflammation and oxidative stress play an important role, and zinc is an important cofactor for the formation of various antioxidant enzymes, which has the effect of fighting free radicals and protecting neurons from oxidative damage.
In addition, zinc is an important nutrient in the central nervous system, especially in the hippocampus and cerebral cortex is rich in zinc if lack of it will affect the balance of the brain, resulting in changes in behavior, learning, memory and emotional stability.
A meta-analysis (23 studies, 1306 cases of Parkinson’s disease and 1294 control group) pointed out that compared with healthy people, patients with Parkinson’s disease have lower levels of zinc in serum and plasma.
*Comment: Zinc deficiency is a potential risk factor for Parkinson’s disease, and zinc supplementation may be a potential treatment, and further clinical studies are needed to confirm its clinical benefit.
11. Zinc improves tinnitus symptoms
Tinnitus is mainly defined as the phantom auditory perception caused by no obvious sound stimulation. The prevalence of adults can reach 25.3%, often causing concentration of attention, insomnia, reduced language resolution, and even physical and mental symptoms such as depression and anxiety, which affects life of very high quality.
Observational studies have found that zinc deficiency is often associated with impaired hearing thresholds and the severity of tinnitus loudness.
A Cochrane Database of Systematic Reviews (contains 3 studies, a total of 209 participants) pointed out that oral zinc did not significantly improve the symptoms of tinnitus in adults (measures include: tinnitus disorder questionnaire, tinnitus Loudness, overall severity).
*Conclusion: As of now, there is no evidence that zinc can improve tinnitus symptoms, and is limited by the small sample size and possible bias. More large-scale experiments with the accurate design are still needed to further verify.
12. Zinc improves acne
Acne vulgaris is a skin disease caused by abnormal hair follicles and sebaceous glands. The population of 11 to 30 years old has a prevalence rate of about 80%. The causative factors are often associated with keratinization of hair follicles, increased secretion of sebaceous glands, and sores Propionibacterium infection is related to inflammation and is more likely to occur in sebaceous glands that are sensitive to hormones, such as face, neck, chest, upper back, and upper arms.
A systematic review pointed out that zinc can help acne by oral or topical use. The underlying mechanism is related to its antibacterial and anti-inflammatory effects, which can reduce sebum secretion.
Another perspective cross-sectional study (for 100 acne patients) pointed out that the lower zinc concentration in the blood may be related to the severity and type of acne.
*Conclusion: Zinc intake may be helpful for acne improvement, but more large-scale experiments are still needed to confirm it.
13. Zinc prevents prostate cancer
Prostate cancer is a common malignant tumor disease in men. According to US statistics, about 180,000 new cases are added every year.
Pathological anatomy found that men’s risk of getting prostate cancer between 40 and 49 years old is about 40%, and it will increase to 70% between 60 and 69 years old.
Although the physiological mechanism that zinc plays in the pathogenesis of prostate cancer is not fully elucidated, the evidence shows that it is related to its ability to inhibit angiogenesis and metastasis of cancer cells.
A meta-analysis (including 17 studies, a total of 11,689 cases of prostate cancer and 111,199 participants) pointed out that although most prostate cancers have insufficient zinc intake; as of now, the dietary intake of zinc and prostate cancer There is no obvious correlation between the two.
*Summary: Ingestion of zinc (whether from food or supplements) does not prevent prostate cancer, and it needs to be confirmed by more large-scale epidemiological studies.
What are the side effects of zinc?
Long-term use of zinc supplements and below the tolerable upper intake (Tolerable Upper Intake Leve) is generally considered safe (tolerable zinc intake for adults is about 40 mg of elemental zinc).
Possible side effects of taking zinc include stomach cramps, loss of appetite, irritability, nausea, vomiting, diarrhea, headache, and a metallic taste in the mouth. These symptoms usually relieve themselves.
Long-term overdose (more than 50 mg or more) may cause symptoms such as fever, fatigue, dizziness, headache, drowsiness, sweating, and low-density lipoprotein.
Clinically, it has also been found that taking more than 50 mg of zinc for 6 to 8 weeks may cause copper deficiency and cause copper deficiency symptoms (such as anemia, osteoporosis), so it is recommended to add 2 mg of copper to the formula to prevent this situation.
In addition, taking more than 100 mg of zinc for a long time not only does no benefit, it may also cause damage to the immune system and increase the incidence of prostate cancer.
Safety Precautions
1. In pregnant women and lactating women with good nutrition status, the intake of zinc supplements should not exceed the tolerable upper limit (40 mg per day).
2. Zinc may affect the efficacy of two types of antibiotics, such as tetracycline antibiotics and quinolones. The relevant drug names are Ciprofloxacin, enoxacin, norfloxacin, sparfloxacin, trovafloxacin, grepafloxacin, demeclocycline, minocycline, tetracycline.
3. Do not take Amiloride (Amiloride, a diuretic) at the same time, it may cause excessive zinc concentration in the blood.
4. Hypertensive drugs (ACE Inhibitors) may reduce the concentration of zinc in the blood.
5. Do not use with the chemotherapeutic drug cisplatin, which may affect the efficacy of the drug.
6. Do not take with immunosuppressants, such as Cyclosporin, Prednisone, Corticosteroids (because zinc has an immune-boosting effect).
7. Do not use with Penicillamine (Wilson’s disease, rheumatoid arthritis common medication), it may affect the efficacy of the drug.
8. When zinc, calcium, magnesium, and iron are absorbed in the intestine, the same transport protein will be used. If the load limit of the transport protein is exceeded, the absorption rate will decrease, so when taking these four minerals at the same time, it is best to add up Less than 800 mg.
Food sources of zinc and recommended dosage
The natural food source of zinc is mainly derived from animal protein, the most abundant content is oysters, followed by red meat, liver, fish, shrimp, eggs, etc., while the plant source is mainly cereals and beans (but the absorption rate is poor).
As for the recommended dosage of zinc, according to the US RDA (Recommended Daily Diet), adult males and females need 11mg and 8mg, respectively, and pregnant and nursing mothers need to increase to 13mg, while children range from 3mg to 9mg.
Where to buy the most recommended zinc supplement?
In recent years, food safety problems in various countries have exploded, and it is not healthy but black-hearted products that everyone spends on. Therefore, European and American products with relatively strict quality control have become popular products.
And iHerb.com is a large-scale medical cosmetics e-commerce company in the United States. It has a high satisfaction rate of 97% in the evaluation of Google customers. It provides global home delivery so that you can buy it without risking buying fakes through purchasing high-quality health products.
