Diet and exercise
GCSE Science A (B1.1.1)
A combination of a balanced diet and regular exercise is needed to help
keep the body healthy. Our bodies provide an excellent environment for
many microbes which can make us ill once they are inside us. Our bodies
need to stop most microbes getting in and deal with any microbes which
do get in. Vaccination can be used to prevent infection.
Candidates should use their skills, knowledge
and understanding to:
■ evaluate information about the effect of food on health
■ evaluate information about the effect of lifestyle on development
■ analyse and evaluate claims made by slimming programmes,
and slimming products.
B1.1.1 Diet and exercise
a) A healthy diet contains the right balance of the different foods you
need and the right amount of energy. Carbohydrates, fats and proteins
are used by the body to release energy and to build cells.
Mineral ions and vitamins are needed in small amounts for healthy
functioning of the body.
A person is malnourished if their diet is not balanced. This may lead to
a person being overweight or underweight. An unbalanced diet may
also lead to deficiency diseases or conditions such as Type 2 diabetes.
b) A person loses mass when the energy content of the food taken in is
less than the amount of energy expended by the body. Exercise
increases the amount of energy expended by the body.
c) The rate at which all the chemical reactions in the cells of the body
are carried out (the metabolic rate) varies with the amount of activity
you do and the proportion of muscle to fat in your body. Metabolic rate
may be affected by inherited factors.
d) Inherited factors also affect our health; for example cholesterol
e) People who exercise regularly are usually healthier than people
who take little exercise.
Nutrient per 100 g
Type of food
Fruits, vegetables, eggs, milk,
Fats and oils
cell growth and repair
Scientists estimate that about one third of cancers in the UK may be linked
Name two other diseases linked to obesity.
The graph shows the changes in the cancer rate and the changes in the
percentage of obese adults in the UK from 1995 to 2006.
Does the data in the graph prove that obesity causes cancer?
Explain the reason for your answer.
Exercise helps a person to lose weight.
Diet and exercise affect health.
4 (a) Many people are obese (very overweight).
Obesity can lead to heart disease.
Other than heart disease, name two conditions which are
linked to obesity.
A European Union report estimates that by 2011, one million
children in the Union will be obese and have raised blood
(a) Body mass is dependent on the metabolic rate of the body.
What is meant by metabolic rate?
(b) Cholesterol is carried around the body by the two types of
lipoprotein: low-density lipoproteins (LDLs) and high-density
Describe the relationship between the two types of lipoproteins and
heart health. (3 marks)
The graph shows the number of deaths from heart disease each year
in the UK.
The pattern for deaths from heart disease in men is different from the
pattern in women.
Give two differences between the patterns for men and women.
Suggest two reasons for the difference in the number of deaths from heart
disease in men and women between the ages of 40 and 60.