Drinking too much zinc daily, especially over 40 mg for adults, can cause short-term issues like nausea, vomiting, diarrhea, headaches, and stomach cramps, while long-term excessive intake can lead to serious problems, primarily copper deficiency, causing neurological issues (numbness/weakness), lower "good" HDL cholesterol, and suppressed immune function, so staying within recommended daily limits is crucial.
According to the National Institutes of Health, 40 mg of zinc a day is the upper limit of a daily dose of zinc taken by mouth for all people age 19 and older. For people 18 and younger, the upper daily limit of zinc varies depending on age.
Both vitamin C and zinc are two of the many essential vitamins and minerals the body needs for optimum health but are especially important during pregnancy. These vitamins and minerals not only help foetal growth but support the immune system to support pregnancy outcomes for both the parent and the growing baby.
Zinc Overdose Symptoms: Nausea and Digestive Issues Nausea, bloating, and appetite loss are common after excess zinc intake. Taking high doses of zinc can irritate the stomach lining, causing nausea, bloating, and reduced appetite. These symptoms may persist for several hours to days depending on the amount ingested.
Adverse Effects
Zinc taken in large amounts may cause diarrhea, abdominal cramps, and vomiting within 3 to 10 hours of swallowing the supplement. The symptoms usually alleviate within a short period. An excess intake of zinc can result in copper or anemia, iron deficiency, or copper deficiency.
Although rare, some individuals, such as those with a history of stomach surgery or prolonged intravenous nutrition, may be at an increased risk for copper deficiency. If you fall into this category, you should avoid taking a zinc supplement because it could decrease your copper levels even more.
Adverse effects of high zinc intake include nausea, vomiting, loss of appetite, abdominal cramps, diarrhea, and headaches. Intakes of 150–450 mg of zinc per day have been associated with such chronic effects as low copper status, altered iron function and reduced immune function.
Recommended time to take: On an empty stomach to maximize absorption, typically in the morning or between meals in the afternoon. Avoid taking it with high-calcium foods or other competing minerals.
Zinc is a mineral that supports overall health. It's found in many foods and drinks, and is also available as a dietary supplement. Taking too much zinc can cause side effects like diarrhea, stomach pain, and vomiting. It's possible to overdose on zinc supplements.
Zinc has anti-inflammatory properties that may protect the skin and help people with acne, rosacea, psoriasis, eczema and wound repair. “Among zinc's plethora of roles, this mineral also aids in wound repair and tissue repair,” Harrison said.
Zinc remains in the system for about two weeks after supplementation has stopped. It is a common supplement taken to shorten the duration of a cold, support the immune system, and encourage wound healing.
Zinc is a critical component in a number of conserved processes that regulate female germ cell growth, fertility, and pregnancy.
Beyond checking for folic acid and iron, look for a prenatal vitamin that contains calcium and vitamin D. They help promote the development of the baby's teeth and bones. It also might be beneficial to look for a prenatal vitamin that contains vitamin C, vitamin A, vitamin E, B vitamins, zinc and iodine.
Early symptoms of zinc deficiency include a loss of appetite and, in infants and children, slowed growth and development. People may lose their hair in patches. They may feel sluggish and irritable. Taste and smell may be impaired.
There is no guarantee that zinc will help you feel better faster. In some studies, zinc did nothing to shorten how long people with colds felt bad. In other studies, zinc may have shortened symptoms by a few days. But the side effects from taking zinc can be uncomfortable or serious in some cases.
Recent research has concluded that zinc serum concentration varies with the amount of sleep, while orally administered zinc increases the amount and the quality of sleep in mice and humans.
Zinc is scientifically proven to support hair growth and repair, but it needs to be the right amount. Most people can get enough zinc through common foods – supplements aren't usually necessary. If you're experiencing hair loss, low zinc levels could be a factor, but it's rarely the sole cause.
Combine zinc with vitamin A, B6, C, and phosphorus. These nutrients enhance zinc absorption. As is the case with iron, avoid taking zinc with calcium, magnesium, or copper. Take zinc 2–3 hours apart from these minerals as they reduce zinc absorption in the intestines.
The food highest in zinc is oysters, which contain significantly more zinc per serving than any other food, followed by other shellfish like crab and lobster, and then red meats such as beef, lamb, and pork. Other excellent sources include poultry, nuts (cashews, pumpkin seeds), legumes (lentils, chickpeas), dairy products, eggs, and fortified cereals, though zinc from plant sources is less easily absorbed.
Because zinc affects so many systems in the body, there is no single distinct symptom of zinc deficiency. Some of the more common symptoms include loss of or diminished smell and taste, poor wound healing, hair loss, roughening of skin/rashes, low libido (men), canker sores, lethargy, and deformed nails.
Those who take high doses of zinc supplements can experience a lack of anagen development, which causes hair loss, but at the same time, one form of zinc treatment can actually encourage hair growth.
While zinc is an essential trace element required for various physiological processes in the body, as mentioned above, excessive amounts of zinc intake can lead to zinc overdose or toxicity. This typically occurs from supplements or denture adhesive creams [51].
The liver is the main organ responsible for the zinc metabolism which can be affected by liver diseases. On the other hand, zinc deficiency may alter hepatocyte functions and also immune responses in inflammatory liver diseases.
You are more likely to have low zinc levels:
Phytate, which is present in staple foods like cereals, corn and rice, has a strong negative effect on zinc absorption from composite meals. Inositol hexaphosphates and pentaphosphates are the phytate forms that exert these negative effects, whereas the lower phosphates have no or little effect on zinc absorption.