Vitamins and minerals are naturally present in the food we eat.
Mr Johnathan Diong, Senior Pharmacist from the Department of Pharmacy at Singapore General Hospital (SGH), a member of the SingHealth group, shares five essential vitamins and why they are good for you.
Iron – Essential for boosting the body’s immune system and an important component of many enzymes. Also functions as an antioxidant
US RDA: 8mg (men), 18mg (women)
Food sources: Red meat such as beef, oysters, shrimp, tuna, lentils, kidney beans and cashew nuts
Excessive intake: Slight excess causes constipation. Higher excesses may result in gastric mucosal ulceration, and increase the likelihood of multi-organ damage
Overdose symptoms: Vomiting and diarrhoea
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Zinc – Essential for boosting the body’s immune system and an important component of many enzymes. Also functions as an antioxidant
US RDA: 11mg (men), 8mg (women)
Food sources: Red meat such as beef, oysters, milk, baked beans and chickpeas
Excessive intake: May result in copper deficiency
Overdose symptoms: Nausea and vomiting
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Vitamin A - Essential for healthy skin, retina and mucous membranes
US RDA: 700mcg (men), 900mcg (women)
Food sources: Yellow and orange vegetables like carrots and pumpkins, spinach, sweet potatoes and cod liver oil.
Excessive intake: May be harmful to skin and bones, causing weakness and brittleness
Overdose symptoms: Tiredness, decreased appetite, vomiting, joint soreness, drying and cracking of lips and skin, hair loss and yellowing of the skin
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Vitamin C - Helps form strong collagen fibres which are essential for the strength and integrity of connective tissue, bones, tendons and ligaments. Also acts as an antioxidant
US RDA: 90mg (men), 75mg (women)
Food sources: Fruits such as oranges, grapefruits and strawberries, vegetables like broccoli and tomatoes
Excessive intake: Increases the likelihood of calcium oxalate kidney stones and can deplete the body of copper, another essential nutrient
Overdose symptoms: Diarrhoea, stomach cramps and nausea
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Calcium – Crucial for maintaining a normal heartbeat and for normal functioning of nerves and muscles. Acts as a building block for bones
US RDA: 1,000mg
Food sources: Dairy products such as milk, cheese and yoghurt, vegetables like broccoli and Chinese cabbage
Excessive intake: May impair kidney function and decrease absorption of other minerals
Overdose symptoms: Nausea, vomiting, loss of appetite and increased urination
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Ref: U11
Check out our other articles on vitamins:
Vitamin A: Benefits and Best Food Sources
Vitamin B: Why Your Body Needs It
Vitamin B: Signs of Deficiency
Vitamin C: Benefits and Top Food Sources
Vitamin D: Food Sources, Supplements and Side Effects
Antioxidants: How It Helps the Body
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