Welcome to the World of Minerals!
In this chapter, we are exploring Minerals. While we need large amounts of "macronutrients" (like protein and carbs), we only need tiny amounts of minerals. Because we need so little, they are called micronutrients.
Think of minerals as the "hidden helpers" or the "spark plugs" of your body. They don't provide energy themselves, but without them, your body’s "engine" wouldn't start or run smoothly. Let’s dive into the six specific minerals you need to know for your OCR GCSE exam!
1. Calcium
Calcium is probably the most famous mineral. About 99% of the calcium in your body is found in your bones and teeth.
What does it do? (Functions)
- Building Strength: It works with phosphorus to make bones and teeth hard and strong.
- Nerve and Muscle Support: It helps your muscles contract and your nerves send messages.
- Blood Clotting: If you cut yourself, calcium helps the blood thicken so you stop bleeding.
Where do we find it? (Sources)
Milk, cheese, and yogurt are the heavy hitters. However, you can also find it in green leafy vegetables (like kale), canned fish with bones (like sardines), and fortified white bread.
What happens if we don’t get enough? (Deficiency)
- Rickets: In children, bones stay soft and can become deformed (bow-legged).
- Osteoporosis: In adults, bones become brittle and break easily. Think of it like a piece of dry honeycomb that snaps under pressure.
Quick Review: Calcium
Key Takeaway: Calcium = Construction. It builds the "scaffolding" of your body (bones).
2. Iron
If calcium is the scaffolding, Iron is the delivery truck.
What does it do? (Functions)
- Oxygen Transport: Iron is used to make haemoglobin in red blood cells. Haemoglobin is like a little taxi that carries oxygen from your lungs to every part of your body.
Where do we find it? (Sources)
- Haem Iron (Animal sources): Red meat, kidney, and liver. This type is easily absorbed by the body.
- Non-Haem Iron (Plant sources): Spinach, beans, lentils, and fortified breakfast cereals.
Did you know? Eating Vitamin C (like an orange) at the same time as plant-based iron helps your body absorb the iron much better!
What happens if we don’t get enough? (Deficiency)
Anaemia: If you don't have enough iron, your "oxygen taxis" can't run. This makes you feel very tired, pale, and short of breath.
Memory Aid: Iron
The symbol for Iron is Fe. If you don't have enough, you Fe-el tired!
3. Sodium (Salt)
Sodium is mostly found in the salt we eat (sodium chloride). While we need some, most people in the UK eat far too much.
What does it do? (Functions)
- Water Balance: It controls the amount of water in your body.
- Nerve Signals: It helps your brain send electrical signals to your muscles.
Where do we find it? (Sources)
Naturally in some foods, but mostly in processed foods like bacon, cheese, crisps, and ready meals.
What happens if we have too much or too little?
- Excess (Too much): This is the most common problem. It can lead to high blood pressure, which increases the risk of heart disease and strokes.
- Deficiency (Too little): Very rare, but can cause muscle cramps after heavy sweating.
Don’t worry if this seems tricky... Just remember that "Sodium" and "Salt" are often used interchangeably in nutrition, and the main danger is having too much.
4. Fluoride
Think of Fluoride as a shield for your mouth.
What does it do? (Functions)
- Tooth Protection: It strengthens tooth enamel (the hard outer layer) to protect against acid and bacteria.
Where do we find it? (Sources)
Drinking water (some areas have it added naturally or by the government), toothpaste, and fish.
What happens if we don’t get enough? (Deficiency)
The main issue is tooth decay. Without fluoride, the enamel is weaker and more likely to get cavities.
5. Iodine
Iodine is the "Metabolism Manager."
What does it do? (Functions)
- Thyroid Function: It helps the thyroid gland in your neck produce hormones that control your metabolism (how fast your body uses energy).
Where do we find it? (Sources)
Seafood, seaweed, and dairy products (cows get iodine from their feed, which ends up in the milk).
What happens if we don’t get enough? (Deficiency)
Goitre: This is where the thyroid gland swells up, causing a large lump in the neck. It can also cause a slow metabolism, making people feel sluggish.
6. Phosphorus
Phosphorus is the best friend of Calcium. They are almost always seen together!
What does it do? (Functions)
- Bone Health: Like calcium, it is essential for strong bones and teeth.
- Energy Release: It helps the body release energy from the food you eat.
Where do we find it? (Sources)
It is in almost all foods, but especially high in meat, fish, dairy, nuts, and beans.
What happens if we don’t get enough? (Deficiency)
It is very rare to have a deficiency because phosphorus is in so many different foods. If it does happen, it causes weak bones and muscles.
Summary Table: The Mineral Cheat Sheet
Use this table for a quick final review before your exam!
Calcium: Bones/Teeth | Milk, Greens | Rickets/Osteoporosis
Iron: Oxygen transport | Red meat, Spinach | Anaemia (Tiredness)
Sodium: Water balance | Salt, Processed food | High Blood Pressure (if excess)
Fluoride: Tooth Enamel | Water, Toothpaste | Tooth Decay
Iodine: Metabolism | Seafood, Dairy | Goitre
Phosphorus: Bones/Energy | Meat, Dairy | Rare (Weak bones)
Common Mistakes to Avoid
- Confusing Calcium and Iron: Remember: Calcium = Bones. Iron = Blood.
- Thinking Sodium is always bad: We need a small amount to live; the problem is only when we eat too much processed food.
- Forgetting Vitamin C: On the exam, if you mention Iron, always try to mention that Vitamin C helps its absorption!
Final Key Takeaway
Minerals are essential micronutrients that keep our structure strong (Calcium/Phosphorus/Fluoride) and our internal systems running (Iron/Sodium/Iodine). A balanced diet with plenty of variety usually provides everything we need!