Zinc plays a crucial role in supporting blood glucose and insulin regulation. It is involved in the synthesis, storage, and release of insulin, the hormone responsible for regulating blood sugar levels. Zinc also enhances the activity of insulin by helping it bind to insulin receptors on cells, facilitating glucose uptake and maintaining stable blood sugar levels. Additionally, zinc has antioxidant properties that can help reduce inflammation and oxidative stress, which are often linked to insulin resistance.
Food Sources of Zinc:
- Oysters and other shellfish
- Red meat (beef, lamb)
- Poultry (chicken, turkey)
- Nuts and seeds (pumpkin seeds, cashews)
- Dairy products (cheese, milk)
Zinc is best absorbed from animal-based sources, but plant-based sources, particularly when consumed in combination with other foods, can also contribute significantly to intake.
Factors That Deplete Zinc:
1. Poor Diet:
Low zinc intake: Diets that are low in zinc-rich foods (such as meat, shellfish, nuts and seeds) can lead to depletion.
High intake of phytates: Phytates, found in grains and legumes, can inhibit zinc absorption.
2. Chronic Illnesses:
Gastrointestinal disorders: Conditions like Crohn’s disease, celiac disease, or chronic diarrhoea can interfere with zinc absorption.
Kidney disease: Impaired kidney function can lead to increased excretion of zinc.
Liver disease: Liver dysfunction can affect zinc metabolism and lead to deficiencies.
Chronic infections or inflammation: These can increase zinc utilisation or loss through urine.
3. Medications:
Diuretics: These increase zinc excretion in urine.
Penicillamine (used in treating rheumatoid arthritis) and some chemotherapy drugs can interfere with zinc absorption or increase its excretion.
4. Alcohol consumption:
Chronic alcohol use can reduce zinc absorption in the intestines and increase zinc excretion through urine.
5. Pregnancy and Lactation:
Pregnant and breastfeeding women may require more zinc, and if their intake is inadequate, they are at higher risk of deficiency.
6. Aging:
Older adults are more likely to have insufficient zinc due to decreased absorption, altered metabolism, and lower dietary intake.
7. Vegetarian and Vegan Diets:
People following strict plant-based diets may be at higher risk because plant foods contain phytates, which reduce the bioavailability of zinc. Plant-based sources of zinc are less easily absorbed by the body compared to animal sources.
Symptoms of Zinc Deficiency:
1. Immune system dysfunction: Increased susceptibility to infections. Slower wound healing.
2. Skin issues: Dermatitis, especially in areas like the face, hands, and feet. Acne-like lesions or rashes (eczema). Hair loss or thinning (alopecia).
3. Cognitive and mood disturbances: Poor concentration, memory problems. Irritability, depression, or anxiety. Impaired taste or smell.
4. Gastrointestinal symptoms: Diarrhoea or gastrointestinal upset. Nausea and vomiting.
6. Hair and nail abnormalities: Brittle or ridged nails. Thinning or loss of hair.
7. Anaemia: Zinc is involved in the production of haemoglobin, and deficiency can lead to mild anaemia.
8. Delayed wound healing: Zinc plays a key role in collagen synthesis, and without enough zinc, wounds may take longer to heal.
Who Is at Risk for Zinc Deficiency:
1. Children and Adolescents: Rapid growth during childhood and adolescence increases the need for zinc, and insufficient intake can lead to deficiency.
2. Pregnant and Breastfeeding Women: Zinc needs are increased during pregnancy and lactation, and deficiency may affect foetal and infant development.
3. Older Adults: Older adults may have lower dietary zinc intake and absorption efficiency.
4. Vegetarians and Vegans: Without careful planning, plant-based diets can lack sufficient bioavailable zinc.
5. People with Malabsorption Disorders: Conditions like celiac disease, Crohn's disease, or other gastrointestinal disorders that affect nutrient absorption.
6. Individuals with Chronic Alcohol Use: Alcohol interferes with zinc absorption and increases its excretion.
7. People with Chronic Illnesses: Those with conditions such as diabetes, kidney disease, liver disease, or autoimmune diseases may be at risk due to increased zinc loss or altered metabolism.
Zinc is an essential mineral for immune function, growth, skin health, and many other physiological processes. Deficiency is more common among specific groups, including vegetarians, pregnant women, the elderly, and those with certain medical conditions. Symptoms can range from mild (e.g., impaired taste or poor appetite) to severe (e.g., immune dysfunction, skin issues, and growth retardation).
