Alpha-GPC is generally considered safe for healthy individuals but if you have a medical condition or are taking any other medications, you should consult a pharmacist or doctor before using it. Observed side effects have included heartburn, headache, insomnia, dizziness, skin rash, cognitive stimulation and confusion. However, these side effects are rare and the risk can be minimised by starting with a low dose and gradually building up if necessary. Research on the use of alpha-GPC during pregnancy or breastfeeding is limited, so it is best to avoid using it in these situations.
Associated risks/scrutiny: ZMA supplements are usually all-natural and there are no known negative side effects. "However, more than 350 mg of magnesium through supplementation can result in diarrhea," Broschart warns. If you are taking medication for your heart or to treat osteoporosis, you should consult your physician before supplementing with magnesium as there may be a drug/nutrient interaction. Vitamin B6 toxicity, can cause neurological effects, but this only occurs when amounts exceed 100 mg per day. Studies have found that zinc ingestion of about 60 mg per day through diet and supplementation can cause copper deficiency.