Zinc Gluconate: Side Effects and Contraindications?

Zinc is a naturally occurring mineral element that is essential for the growth and development of the body's tissues. Furthermore, it plays a role in numerous enzymatic reactions, including the metabolism of proteins, lipids, and carbohydrates. Present in small quantities in the human body, zinc stimulates the immune system. The body's zinc intake is primarily ensured through diet and sometimes through the consumption of dietary supplements.

Zinc, being unstable, cannot be directly incorporated into cosmetic products. It is therefore transformed into zinc gluconate, whose chemical formula is C12H22O14Zn. This active ingredient is formed of two gluconate anions, each carrying a negative charge, for each zinc cation, carrying two positive charges. The zinc gluconate is primarily known for its anti-inflammatory properties and its matifying effects, making it an ally for acne-prone skin.

However, these are not its only properties. Indeed, the zinc gluconate is also an excellent antioxidant, capable of protecting cells and tissues from oxidative stress and preventing their premature ageing. Finally, it should be noted that this active ingredient is also incorporated into hair care products, due to its anti-dandruff properties and its inhibitory effect on hair loss.

Zinc gluconate is typically available in the form of topical treatments, but can also be found as dietary supplements. There are no known adverse effects associated with the skin or hair application of zinc gluconate. This active ingredient is considered safe by European regulations (Regulation (EC) No 1223/2009). Zinc gluconate is incorporated at rates between 0.1 and 5% in skincare products as the zinc concentration should not exceed 1%. It's also worth noting that the topical application of zinc gluconate is not advised against for pregnant and/or breastfeeding women, and this active ingredient is not photosensitising.

Regarding its oral intake, it's worth noting that zinc gluconate rarely causes adverse effects when consumed in proportions recommended by doctors. Furthermore, while zinc gluconate intake is feasible for pregnant and/or breastfeeding women, we still recommend seeking advice from your doctor beforehand. Among the rare side effects reported following the oral intake of zinc gluconate, we can mention abdominal pain, nausea, and skin rashes. It is generally recommended not to exceed 30 mg of zinc per day, which equates to 208 mg of zinc gluconate.

Furthermore, it is advised against consuming this active ingredient in conjunction with antibiotics from the cycline or quinolone families, digestive dressings, or medications containing calcium or iron. If this applies to you and you wish to take dietary supplements based on zinc gluconate, seek advice from your doctor so they can guide you and tell you if the combination you are considering is possible.

A clinical case has recently highlighted the dangers associated with excessive ingestion of zinc gluconate. Over a twelve-month period, a young woman consumed approximately 2000 mg of zinc gluconate daily. She subsequently developed a anaemia corresponding to a copper deficiency induced by zinc and a severe nephrosis, which is a degenerative and non-inflammatory lesion of the kidney tissue. Following the cessation of zinc gluconate ingestion, both the anaemia and nephrosis were resolved. This case underscores the importance of adhering to prescribed dosages when it comes to oral intake of a medication or dietary supplement, as zinc gluconate is a potent active ingredient.

• HEIN M. Copper deficiency anemia and nephrosis in zinc-toxicity: a case report. South Dakota journal of medicine (2003).

• ORTONNE J. P. Évaluation du potentiel photosensibilisant du gluconate de zinc. Annales de dermatologie et de vénéréologie (2008).