Zinc

Zinc is an essential trace mineral — the body cannot make or store it in large amounts, so a consistent dietary or supplemental supply is needed. It is required for the function of more than 300 enzymes and plays a foundational role across multiple body systems.

• Enzymes and metabolism — a cofactor for enzymes governing digestion, protein synthesis, and energy pathways
• Immune system — essential for the development and activation of T-cells and B-cells
• Cell division and DNA — involved in DNA repair, tissue growth, and wound healing
• Senses of taste and smell — zinc deficiency can impair taste and smell perception

Good dietary sources include oysters, red meat, legumes, nuts, seeds, and fortified cereals. Zinc from plant sources is less bioavailable than from animal sources due to phytate inhibition.

Zinc (ซิงค์) has been studied across several areas of health support:

• Immunity and colds — supports immune cell function; research suggests zinc supplementation may shorten the duration and severity of the common cold, especially in lozenge form
• Skin and acne — regulates sebum and has anti-inflammatory properties; studies show zinc may help reduce the severity of acne vulgaris, though it is less potent than oral antibiotics
• Wound healing — essential for collagen synthesis and skin cell division, supporting the healing process
• Male reproductive health — contributes to testosterone production and sperm quality
• Senses and eye health — supports night vision and maintains the senses of taste and smell

Zinc is a dietary supplement, not a medication. Benefits are most significant in individuals who are genuinely deficient. If unsure whether you are zinc-deficient, consult a pharmacist before supplementing.

The general recommended dietary allowance (RDA) for zinc in adults is 8–11 mg/day, while supplemental doses typically range from 15–30 mg/day depending on purpose and form.

• Best time to take — zinc is best absorbed on an empty stomach (1 hour before or 2 hours after meals). If nausea occurs, take with food instead
• Avoid combining with — high-calcium foods or dairy, high-phytate whole grains, and high-dose iron supplements, all of which can compete with zinc absorption
• Upper Tolerable Intake Level (UL) for adults — 40 mg/day. Chronic intake above this level can impair copper absorption
• Duration — consult a pharmacist if planning to supplement for more than 3–4 months continuously

For zinc lozenges (e.g. MYBACIN), allow the tablet to dissolve slowly in the mouth as directed. Do not chew or swallow immediately — direct contact with throat mucosa is part of the intended mechanism.

Zinc is generally safe at appropriate doses, but there are side effects and risks to know:

• Nausea and GI discomfort — most common, especially when taken on an empty stomach. Taking with food reduces this significantly
• Acute zinc excess — severe nausea, vomiting, stomach cramps, and fatigue, typically from single doses above 150–450 mg
• Chronic excess (>40 mg/day long-term) — impairs copper absorption, leading to copper deficiency which can affect the blood and nervous system; may also lower HDL (good) cholesterol
• Drug interactions — zinc reduces absorption of tetracycline and quinolone antibiotics. Separate intake by at least 2 hours if taking these medications

If severe nausea occurs after taking zinc, stop and consult a pharmacist or doctor — especially for individuals on multiple medications.

Not everyone needs zinc supplementation. Consider individual risk factors and needs:

Groups who may benefit from zinc supplementation:

• Vegetarians and vegans — plant-based zinc is less bioavailable; higher deficiency risk compared to omnivores
• Older adults — absorption and retention decrease with age
• Pregnant and breastfeeding women — zinc requirements increase; only supplement under medical guidance at appropriate doses
• People with GI conditions — Crohn's disease or malabsorption syndromes reduce zinc uptake
• Heavy alcohol consumers — alcohol reduces zinc absorption and increases urinary zinc loss

Groups who should consult a doctor or pharmacist first:

• Those taking tetracycline or quinolone antibiotics
• Those taking penicillamine (rheumatoid arthritis treatment)
• Individuals with chronic kidney disease
• Those already supplementing high-dose iron

Zinc comes in several forms — choosing the right one can make a meaningful difference in absorption and tolerability.

• Zinc Gluconate — the most widely available form, reasonably well absorbed, and affordable. Commonly found in lozenges for cold and throat support (e.g. MYBACIN)
• Zinc Picolinate — bound to picolinic acid, a compound naturally produced in the body. Some studies suggest better absorption than gluconate, though evidence remains mixed
• Zinc Bisglycinate (Amino Acid Chelate) — bound to the amino acid glycine; highly bioavailable and gentler on the stomach than inorganic forms. A good choice for those with sensitive digestion
• Zinc Oxide — lowest cost but poorest bioavailability; primarily used in topical formulations
• Zinc Sulfate — an older medical-grade form with moderate absorption but more GI irritation than chelate forms

For those prioritising absorption and stomach comfort, bisglycinate or picolinate are preferred. For cost-effectiveness, gluconate is a solid choice. Consult a pharmacist for personalised guidance.

The answer to "which zinc brand is best" depends on the form, dosage, and intended use. Popular brands available in the Thai market include:

• BLACKMORES Bio Zinc — zinc amino acid chelate combined with magnesium and vitamin B6, targeting skin health and hormonal balance; a well-known Australian brand
• ONSET Zinc — Thai brand with zinc gluconate; accessible price point
• AMSEL Zinc — Thai zinc gluconate focused on immunity and skin
• MYBACIN — zinc gluconate + vitamin C lozenge for cold and throat support; must be dissolved slowly in the mouth rather than swallowed

Generic zinc supplements with the same active ingredient and form can be excellent value. What matters most is the zinc form (gluconate / picolinate / bisglycinate) and the elemental zinc content per tablet — not just the brand name. Consult a pharmacist for guidance based on your budget and health goals.