Nutritional needs and health

Welcome to Your Guide on Nutritional Needs and Health!

In this chapter, we are going to explore how the food we eat affects our bodies and why our needs change as we get older. We’ll also look at how to plan meals for different groups of people and how to avoid health problems like heart disease or brittle bones. Think of your body as a high-performance machine; the food you eat is the fuel, and this chapter teaches you how to choose the right fuel for the job!

1. Making Informed Choices: A Balanced Diet

To stay healthy, we need to eat a variety of foods in the right amounts. In the UK, we use the Eatwell Guide as our main blueprint for healthy eating.

The Eatwell Guide Basics

The guide shows us five main groups. Most of our plate should be Fruit and Vegetables and Starchy Carbohydrates (like potatoes, bread, and pasta). We need smaller amounts of Protein (beans, fish, meat) and Dairy. We only need a tiny amount of Oils and Spreads.

Nutritional Needs at Different Life Stages

Our bodies have different requirements depending on how old we are. Don't worry if this seems like a lot to remember—just think about what the body is "doing" at that age:

• Young Children: They are growing fast and are very active. They need energy-dense foods (lots of energy in small portions) because their tummies are small. They also need Calcium and Vitamin D for bone growth.
• Teenagers: This is the time of "growth spurts" and hormonal changes. Boys often need more Protein for muscle development, and girls need extra Iron to replace what is lost during menstruation.
• Adults: Growth has stopped, so the focus is on maintenance. Adults should focus on a balanced diet to avoid weight gain.
• The Elderly: They are usually less active, so they need less energy (fewer calories). However, they need plenty of fibre to help digestion and Vitamin B12 to keep their brains healthy.

Planning for Special Dietary Groups

Sometimes people choose or need to eat differently:

• Vegetarians/Vegans: They don't eat meat (vegetarians) or any animal products at all (vegans). They must find alternative protein sources like beans, lentils, or tofu.
• Coeliacs: These people have an intolerance to gluten (found in wheat, barley, and rye). They must eat gluten-free flour and grains.
• Lactose Intolerant: Their bodies cannot digest the sugar in milk (lactose). They use alternatives like soya, almond, or oat milk.
• High Fibre Diets: Often recommended to prevent constipation and reduce the risk of bowel cancer.

Quick Review: The Eatwell Guide is for everyone. Children need energy for growth; teenagers need iron and protein; the elderly need less energy but high-quality nutrients.

Key Takeaway: Balance is key! Use the Eatwell Guide to ensure you get the right proportions of food groups for your specific age and lifestyle.

2. Understanding Energy Needs

Energy is the "fuel" that keeps us moving and keeps our heart beating. But how much do we actually need?

BMR and PAL

There are two main things that decide your energy needs:

1. Basal Metabolic Rate (BMR): This is the amount of energy your body needs just to stay alive while you are resting (to keep your heart beating and lungs breathing).
2. Physical Activity Level (PAL): This is how much extra energy you use when you move around, exercise, or work.

Total Energy Requirement = BMR + PAL

Achieving "Energy Balance"

Think of it like a set of weighing scales:
• If Energy In (food) is equal to Energy Out (BMR + PAL), your weight stays the same.
• If Energy In is higher, you gain weight.
• If Energy Out is higher, you lose weight.

The "Golden Percentages" for Energy

The government recommends that our daily energy should come from these specific sources:

• Protein: \(15\%\)
• Fat: \(35\%\) or less
• Carbohydrates: \(50\%\)
(Within carbohydrates, 45% should be from starches/natural sugars and only a maximum of 5% from "free sugars" like sweets or soda).

Did you know? Muscle burns more energy than fat, even when you are sleeping! This means people with more muscle usually have a higher BMR.

Key Takeaway: Your energy needs depend on your age, gender, and how active you are. Most of your energy should come from starchy carbohydrates, not fats or sugars.

3. Nutritional Analysis and Modifying Recipes

We can use food tables or computer software to calculate exactly how much fat, sugar, or energy is in a meal. This helps us "tweak" recipes to make them healthier.

How to "Health-Check" a Recipe

If a recipe is too high in fat or low in vitamins, you can modify it:
• Swap the Method: Instead of frying chicken (adds fat), try grilling or steaming it.
• Change Ingredients: Swap white flour for wholemeal flour to increase fibre.
• Reduce Salt: Use herbs and spices for flavour instead of adding extra salt (sodium).

Common Mistake: Many students think "fat-free" always means healthy. Sometimes fat-free foods have lots of added sugar to make them taste better. Always check the whole label!

4. Diet, Nutrition and Health Risks

If we don't follow the guidelines, we can develop diet-related health risks. Here are the main ones you need to know:

Obesity

This happens when someone consistently consumes more energy than they use. It can lead to other serious problems like Type 2 Diabetes and Heart Disease.

Cardiovascular Health

• Coronary Heart Disease (CHD): Often caused by eating too much saturated fat, which clogs the arteries (the pipes carrying blood).
• High Blood Pressure: Often linked to eating too much salt. This puts strain on the heart.

Bone Health

• Rickets: In children, a lack of Vitamin D or Calcium makes bones soft and leg bones may bow outward.
• Osteoporosis: In older adults, bones become brittle and break easily. Think of it like a honeycomb—in osteoporosis, the holes in the honeycomb get too big.

Other Important Conditions

• Type 2 Diabetes: Often linked to being overweight. The body can't control blood sugar levels properly.
• Iron Deficiency Anaemia: A lack of iron means the blood can't carry enough oxygen. This makes people feel very tired and pale.
• Dental Health: Too much "free sugar" (sweets, fizzy drinks) leads to tooth decay.

Memory Aid: "A-B-C" for Health
Anaemia = Iron (Iron Man has strong blood!)
Bones = Calcium (Calcium/Cold Milk)
CHD = Fat (Fats clog the heart)

Key Takeaway: Many health problems are preventable. By reducing saturated fat, salt, and sugar, and increasing fibre and vitamins, we can lower the risk of these diseases.

Quick Review Quiz (Mental Check!)

1. Which life stage needs extra iron for menstruation? (Answer: Teenager girls)
2. What does PAL stand for? (Answer: Physical Activity Level)
3. Too much saturated fat is a risk factor for which disease? (Answer: Coronary Heart Disease)
4. What percentage of our daily energy should come from fat? (Answer: 35% or less)

Great job! You've covered the essentials of nutritional needs and health. Remember, it's all about balance, energy in vs energy out, and making smart swaps in the kitchen!