Bone Health, Dental Health and Anaemia

This lesson covers three important diet-related health conditions: bone diseases (rickets and osteoporosis), dental health (tooth decay), and iron deficiency anaemia, as required by AQA GCSE Food Preparation and Nutrition specification 8585, section 3.2.3. You must understand the nutritional causes, the groups most at risk, and how diet can prevent and manage each condition.

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Bone Health

The Role of Calcium and Vitamin D

Healthy bones require two key nutrients working together:

• Calcium — the main mineral in bones and teeth. Approximately 99% of the body's calcium is stored in the skeleton. Calcium gives bones their strength and rigidity.
• Vitamin D — essential for the absorption of calcium from the small intestine. Without sufficient vitamin D, the body cannot absorb enough calcium from food, even if dietary calcium is adequate.

Nutrient	RNI (Adults)	Best Sources
Calcium	700 mg/day	Milk, cheese, yoghurt, fortified plant milks, tinned fish with bones (sardines, salmon), tofu set with calcium, kale, broccoli
Vitamin D	10 µg/day (all adults in the UK, recommended as a supplement in autumn/winter)	Sunlight on skin (main source), oily fish, eggs, fortified cereals, fortified spreads, supplements

Exam Tip: Always link calcium and vitamin D together when discussing bone health. Calcium provides the building material; vitamin D enables the body to absorb it. Mentioning one without the other is incomplete and may cost marks.

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Rickets

Rickets is a condition affecting children in which the bones become soft and weak, leading to bowed legs, delayed growth, bone pain, and skeletal deformities. It is caused by a severe deficiency of vitamin D and/or calcium.

Feature	Details
Who is affected	Children, especially those aged 6 months to 3 years
Cause	Deficiency of vitamin D (and sometimes calcium)
Symptoms	Soft, weak bones; bowed legs; swollen wrists and ankles; delayed growth; bone pain; dental problems
Why vitamin D deficiency occurs	Limited sunlight exposure (indoor lifestyle, covering skin, living at northern latitudes like the UK); dark skin (less efficient at producing vitamin D from sunlight); inadequate dietary intake
Prevention	Vitamin D supplements for all children aged 6 months to 5 years (UK government recommendation); adequate calcium intake; some sunlight exposure; vitamin D-rich and fortified foods

Rickets had largely been eradicated in the UK by the mid-20th century through improved nutrition and vitamin supplementation, but cases have been increasing in recent years, particularly among children with dark skin and those with limited sun exposure.

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Osteoporosis

Osteoporosis is a condition affecting mainly older adults (especially post-menopausal women) in which the bones become brittle and fragile, increasing the risk of fractures, particularly of the hip, spine, and wrist.

Feature	Details
Who is affected	Mainly women after the menopause (due to the drop in oestrogen, which protects bone density); also men over 70; people with very low body weight; people with a family history
Cause	Loss of bone density over time. Insufficient calcium and vitamin D intake, especially during childhood and adolescence (when peak bone mass is built), and in later life
Symptoms	Often no symptoms until a fracture occurs. Can cause loss of height, stooped posture (kyphosis), back pain
Risk factors	Low calcium/vitamin D intake, lack of weight-bearing exercise, smoking, excessive alcohol, low body weight, family history, early menopause
Prevention	Building peak bone mass during childhood and adolescence (high calcium and vitamin D intake, weight-bearing exercise); maintaining calcium and vitamin D intake in adulthood; vitamin D supplements (10 µg/day for all adults over 65); weight-bearing exercise throughout life

graph TD
    A["Bone Health"] --> B["Rickets<br/>(children)"]
    A --> C["Osteoporosis<br/>(elderly / post-menopausal)"]

    B --> B1["Cause: Vitamin D / calcium<br/>deficiency"]
    B --> B2["Symptoms: Soft bones,<br/>bowed legs, delayed growth"]
    B --> B3["Prevention: Supplements,<br/>sunlight, fortified foods"]

    C --> C1["Cause: Loss of bone<br/>density over time"]
    C --> C2["Symptoms: Fragile bones,<br/>fractures, stooped posture"]
    C --> C3["Prevention: Peak bone mass<br/>in youth, calcium + vitamin D,<br/>weight-bearing exercise"]

    style A fill:#2c3e50,color:#fff
    style B fill:#e67e22,color:#fff
    style C fill:#8e44ad,color:#fff
    style B3 fill:#27ae60,color:#fff
    style C3 fill:#27ae60,color:#fff

Comparing Rickets and Osteoporosis

Feature	Rickets	Osteoporosis
Age group	Children	Elderly (especially post-menopausal women)
Bones become	Soft and weak	Brittle and fragile
Key deficiency	Vitamin D (± calcium)	Calcium and vitamin D (accumulated over years)
Symptoms	Bowed legs, delayed growth, bone pain	Fractures, loss of height, stooped posture
Prevention	Vitamin D supplements, calcium, sunlight	Peak bone mass in youth, calcium, vitamin D, exercise
Reversible?	Yes, with treatment (supplements and dietary changes)	Bone loss can be slowed but not fully reversed

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Dental Health

How Diet Affects Teeth

Teeth are covered by enamel, the hardest substance in the body. Despite its hardness, enamel can be destroyed by acid produced when bacteria in the mouth feed on sugar. This process is called dental caries (tooth decay).

The Process of Tooth Decay

1. Bacteria in the mouth (in dental plaque) feed on free sugars from food and drink.
2. The bacteria produce acid as a waste product.
3. The acid attacks and dissolves the tooth enamel (demineralisation).
4. If this process is repeated frequently (e.g. snacking on sugary foods throughout the day), the enamel is destroyed faster than saliva can repair it (remineralisation).
5. A cavity (hole) forms in the tooth.
6. If untreated, the decay can reach the inner layers of the tooth (dentine and pulp), causing pain, infection, and potentially tooth loss.

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Dietary Factors That Increase Tooth Decay Risk

Factor	Explanation
Frequency of sugar consumption	The number of times sugar is consumed is more important than the total amount. Each time sugar is eaten, acid attacks the teeth for about 20–30 minutes. Frequent snacking or sipping sugary drinks means teeth are under constant acid attack.
Sticky, sugary foods	Toffee, dried fruit, sweets that stay in the mouth for a long time give bacteria more sugar to feed on.
Sugary drinks	Fizzy drinks, fruit juice, sports drinks, and smoothies all contain free sugars and are often acidic themselves. Sipping them throughout the day is particularly damaging.
Hidden sugars	Many processed foods contain surprising amounts of sugar: ketchup, baked beans, breakfast cereals, yoghurt, bread.
Acidic foods and drinks	Citrus fruits, vinegar, carbonated drinks can erode enamel directly (dental erosion), even without bacteria.

Exam Tip: The key message for dental health is that frequency of sugar consumption matters more than quantity. Three biscuits eaten at once cause one acid attack. Three biscuits eaten at three different times cause three separate acid attacks. This is a very commonly examined point.

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Preventing Tooth Decay Through Diet