Medino Review 2026: Worth the Price?

Possible side effects

• High-dose iron supplements can cause stomach upset, constipation, nausea, abdominal pain, vomiting, and diarrhea.
• Supplements with 25 mg iron or more can reduce zinc absorption and plasma zinc concentrations.

Serious risks

• Large acute intakes from supplements or medicines can lead to corrosive necrosis of the intestine, which might lead to fluid and blood loss, shock, tissue damage, and organ failure.
• In severe cases, iron overdoses can lead to multisystem organ failure, coma, convulsions, and even death.
• Case reports suggest some people develop more serious gastrointestinal effects, including gastritis and gastric lesions.
• At least 43 U.S. children died between 1983 and 2000 from ingesting high-dose iron supplements.
• Without treatment, people with hereditary hemochromatosis typically develop signs of iron toxicity by their 30s.
• Iron toxicity effects in hemochromatosis can include liver cirrhosis, hepatocellular carcinoma, heart disease, and impaired pancreatic function.

Avoid or ask a doctor first if

• People with hemochromatosis: treatment guidance includes avoiding iron and vitamin C supplements.
• The required FDA label on solid iron supplements says accidental overdose is a leading cause of fatal poisoning in children under 6, and to keep the product out of children's reach.

Medication interactions

• Iron supplements may interact with levodopa and levothyroxine.
• Proton pump inhibitors can potentially reduce iron absorption.

Possible side effects

• High iodine intakes can cause goiter, elevated TSH levels, and hypothyroidism, some of the same symptoms as iodine deficiency.

Serious risks

• Iodine-induced hyperthyroidism can result from high iodine intakes, including when iodine is given to treat iodine deficiency.
• Studies have shown that excessive iodine intakes cause thyroiditis and thyroid papillary cancer.
• Acute iodine poisoning is rare and is usually caused by doses of many grams. Symptoms include burning of the mouth, throat, and stomach, fever, abdominal pain, nausea, vomiting, diarrhea, weak pulse, and coma.
• Long-term intakes above the UL increase the risk of adverse health effects.

Avoid or ask a doctor first if

• People with autoimmune thyroid disease or iodine deficiency may have adverse effects at iodine intakes considered safe for the general population.
• The ULs do not apply to people receiving iodine for medical treatment, who should be under a physician's care.

Medication interactions

• Iodine supplements have the potential to interact with several types of medications. People taking these medications on a regular basis should discuss their iodine intakes with their health care providers.

Possible side effects

• High doses from supplements or medications can cause diarrhea, nausea, and abdominal cramping.
• Magnesium carbonate, chloride, gluconate, and oxide are the forms most commonly reported to cause diarrhea.

Serious risks

• Very high doses can lead to magnesium toxicity, with low blood pressure, vomiting, difficulty breathing, irregular heartbeat, cardiac arrest and other signs.
• A few cases of fatal hypermagnesemia have been reported.
• Very large doses of magnesium-containing laxatives and antacids have been associated with magnesium toxicity.
• The risk of toxicity increases with impaired kidney function or kidney failure.

Avoid or ask a doctor first if

• People with impaired kidney function or kidney failure face higher risk of magnesium toxicity.
• People taking medications regularly should discuss their magnesium intake with their health care providers.

Medication interactions

• Magnesium may interact with oral bisphosphonates, tetracyclines, and quinolone antibiotics.
• Some medications, including diuretics and proton pump inhibitors, can affect magnesium status.

Possible side effects

• High zinc intakes can cause nausea, dizziness, headaches, gastric distress, vomiting, and loss of appetite.

Serious risks

• Doses of 50 mg or more taken for weeks can interfere with copper absorption, reduce immune function, and lower HDL cholesterol.
• Very high supplemental doses (142 mg/day) might interfere with magnesium absorption and disrupt magnesium balance.
• According to a few reports, overuse of zinc-containing denture adhesive creams can lead to neurological symptoms and anemia.

Avoid or ask a doctor first if

• The upper limits don't apply to people receiving zinc for medical treatment, who should be under a physician's care.
• Zinc-free denture adhesive formulations are available to prevent the effects linked to zinc-containing creams.

Medication interactions

• Zinc may interact with quinolone antibiotics, tetracycline antibiotics, and penicillamine.
• Some diuretics can lower serum zinc by increasing zinc excretion in urine.
• People taking medications regularly should discuss their zinc status with their health care providers.

Possible side effects

• Early signs of too much selenium are a garlic odor on the breath and a metallic taste in the mouth.
• Hair loss and nail brittleness or loss are the most common clinical signs of chronically high selenium intake.
• Other signs of chronically high intake include skin rash, nausea, diarrhea, fatigue, irritability, and nervous system abnormalities.

Serious risks

• Acute selenium toxicity can cause severe gastrointestinal and neurological symptoms, respiratory distress syndrome, heart attack, kidney failure, cardiac failure, and, in rare cases, death.
• Acute toxicity has resulted from misformulated over-the-counter products containing very large amounts of selenium. In 2008, 201 people had severe adverse reactions to a liquid supplement with 200 times the labeled amount.
• Brazil nuts contain very high amounts of selenium and could cause selenium toxicity if eaten regularly.

Avoid or ask a doctor first if

• The upper limits do not apply to people taking selenium under a physician's care.
• People who take medications regularly should discuss their selenium status with their health care providers.

Medication interactions

• Selenium supplements may interact with medications, and some medications, such as cisplatin, can affect selenium levels in the body.

Possible side effects

• High copper exposure over time can cause gastrointestinal symptoms.

Serious risks

• Chronic exposure to high levels of copper can result in liver damage.
• Copper toxicity has been reported in people who drink water with high copper levels, for example from stagnant water in copper-containing pipes and fixtures.
• People with Wilson's disease can develop neurologic and liver damage that can result in cirrhosis.

Avoid or ask a doctor first if

• People with Wilson's disease have a high risk of copper toxicity.

Medication interactions

• Copper is not known to have any clinically relevant interactions with medications.

Serious risks

• Manganese toxicity mainly affects the central nervous system and can cause tremors, muscle spasms, tinnitus, hearing loss, and unsteadiness on one's feet.
• People who drink water with high manganese levels have also developed manganese toxicity.
• Workers such as welders and miners who chronically inhaled manganese dust have developed manganese toxicity.
• Toxicity signs and symptoms can progress to Parkinson's-like neuromotor impairments, including changes in gait and balance, tremor, and rigidity.

Avoid or ask a doctor first if

• People with chronic liver disease eliminate manganese less well in bile and are more susceptible to its neurotoxicity and other adverse effects of excess intake.
• Iron deficiency increases manganese absorption and can worsen symptoms of manganese toxicity.

Medication interactions

• Manganese is not known to have any clinically relevant interactions with medications.

Serious risks

• Isolated case reports link chromium supplements to several problems, including liver dysfunction and renal failure.
• The FNB said caution may be warranted because data are limited, and high intakes could have adverse effects.

Avoid or ask a doctor first if

• People with renal or liver disease might be susceptible to adverse effects from high chromium intakes.

Medication interactions

• Several types of medications have the potential to interact with chromium supplements.
• People taking medications regularly should talk with their health care providers about their chromium intakes.

Serious risks

• Acute molybdenum toxicity is rare but can occur with industrial mining and metalworking exposure.
• In one study of high dietary molybdenum intake in an area of Armenia, affected people had achy joints, gout-like symptoms, and abnormally high blood uric acid.

Avoid or ask a doctor first if

• Infants up to 12 months should get molybdenum only from breast milk, formula, and food.

Medication interactions

• The source says molybdenum has no known, clinically relevant, interactions with medications.

Possible side effects

• Accidental swallowing of boric acid or borax, found in some household cleaners and pesticides, is linked to digestive, skin and nervous system symptoms.
• Boron toxicity can also cause headache, hypothermia, restlessness, and other symptoms.

Serious risks

• Extremely high doses of boron can be fatal in adults.
• In infants, high boron intakes have caused anemia, seizures, erythema, and thin hair.
• The upper limits are based on reproductive and developmental effects seen in animals.

Avoid or ask a doctor first if

• Infants should get boron only from breast milk, formula, and food.

Medication interactions

• Boron is not known to have any clinically relevant interactions with medications.