Micronutrients and Hydration

While macronutrients provide energy, micronutrients — vitamins and minerals — and water are equally essential for health and sporting performance. The Edexcel GCSE PE specification requires you to understand the role of key vitamins, minerals, water and fibre, and the consequences of deficiency or inadequate hydration.

---

What Are Micronutrients?

"Micro" means small — micronutrients are needed in small amounts but are essential for the body to function properly. They do not provide energy but enable chemical reactions, support growth, and protect against illness.

---

Vitamins

Vitamin	Function	Food Sources	Deficiency Consequence
Vitamin A	Healthy vision, skin and immune function	Carrots, sweet potatoes, liver, eggs	Night blindness, weakened immune system
Vitamin B group	Energy release from food; nervous system function	Whole grains, meat, eggs, dairy	Fatigue, anaemia, poor energy levels
Vitamin C	Immune function, skin health, wound healing, antioxidant	Citrus fruits, peppers, broccoli, strawberries	Scurvy, poor wound healing, weakened immunity
Vitamin D	Calcium absorption, bone health	Sunlight, oily fish, eggs, fortified foods	Rickets (children), osteomalacia (adults), weak bones
Vitamin E	Antioxidant, protects cell membranes	Nuts, seeds, vegetable oils	Rare; muscle weakness, impaired immune function
Vitamin K	Blood clotting	Green leafy vegetables, broccoli	Poor blood clotting, excessive bleeding

Fat-Soluble vs Water-Soluble Vitamins

Category	Vitamins	Key Feature
Fat-soluble	A, D, E, K	Stored in the body's fat tissue; do not need to be consumed every day
Water-soluble	B group, C	Not stored in the body; must be consumed regularly; excess is excreted in urine

---

Minerals

Mineral	Function	Food Sources	Deficiency Consequence
Calcium	Strong bones and teeth; muscle contraction; blood clotting	Milk, cheese, yoghurt, green leafy vegetables	Osteoporosis, weak bones, muscle cramps
Iron	Forms haemoglobin in red blood cells; carries oxygen in the blood	Red meat, spinach, beans, fortified cereals	Anaemia (tiredness, breathlessness, reduced endurance)
Sodium	Nerve function; fluid balance; muscle contraction	Salt, processed foods, cheese	Cramps, hyponatraemia (rare but dangerous)
Potassium	Muscle contraction; heart function; fluid balance	Bananas, potatoes, avocados	Muscle weakness, cramps, irregular heartbeat

Exam Tip: Iron and calcium are the two minerals most commonly tested in Edexcel GCSE PE. Make sure you know their functions, sources and deficiency consequences. Iron is particularly important for aerobic performance because it is essential for oxygen transport in the blood.

---

Water and Hydration

Water is essential for every bodily function. The body is approximately 60% water, and even small levels of dehydration significantly impair performance.

Functions of Water