​​​​​5 Essential Vitamins: Iron, Zinc, Vitamin A and More
5 Essential Vitamins: Iron, Zinc, Vitamin A and More

Vitamins ​and minerals​ are naturally present in the food we eat.​

Mr Johnathan Diong, Senior Pha​rmacist from the Department of Pharmacyopens in a new tab at Singapore General​ Hospitalopens in a new tab (SGH), a member of the SingHealth​opens in a new tab group, shares five essential vitamins and why they are good for you.

Iron – Es​sential for boostin​g 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: Re​d m​eat 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 like​liho​od of multi-organ damage
Overdose symptoms: Vomiting and diarrhoea 

​​Iron

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

Zinc

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​

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

Vitamin C

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
F​ood 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

Calcium

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Ref: U11​

Check out our other articles on vitamins:

Vitamin A: Benefits and Best Food Sourcesopens in a new tab

Vitamin B: Why Your Body Needs Itopens in a new tab

Vitamin B: Signs of Deficiencyopens in a new tab

Vitamin C: Benefits and Top Food Sourcesopens in a new tab

Vitamin D: Food Sources, Supplements and Side Effectsopens in a new tab

Antioxidants: How It Helps the Bodyopens in a new tab

Antioxidants and Cancer Preventionopens in a new tab

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