A.3 Special issues in human nutrition

A.3 Special issues in human nutrition

·       A.3.1 Distinguish between the composition of human milk and artificial milk used for bottle-feeding babies

·       A.3.2 Discuss the benefits of breastfeeding

·       A.3.3 Outline the causes and symptoms of type II diabetes

·       A.3.4 Explain the dietary advice that should be given to a patient who has developed type II diabetes

·       A.3.5 Discuss the ethical issues concerning the eating of animal products, including honey, eggs, milk and meat.

·       A.3.6 Evaluate the benefits of reducing dietary cholesterol in lowering the risk of coronary heart disease.

·       A.3.7 Discuss the concept of food miles and the reasons for consumers choosing foods to minimise food miles

A.3.1

Human milk	Powdered (artificial milk)
Enzymes amylase and lipase	Contains soya/bovine (cow) proteins
White blood cells (macrophages)	Fatty acids derived from vegetable oil.
Antibodies	Contains glucose rather than lactose
Hormones	Doesn’t contain antibodies.
About 50% more lactose to give the baby energy. Has more cholesterol (build cell membranes). High levels of lipids to construct phospholipids for new cells.
Lower levels of protein than cow’s milk. Higher levels of taurine for brain development.
More iron in formula than in human milk.

A.3.2

·       Human milk is species-specific. Meets baby’s nutritional needs at that early stage. It is also easier to digest for the baby.

·       May aid in mother-infant bonding and communication, reduces post-partum depression

·       Contain high levels of antibodies, protecting infants from infections. The risk of allergies is not present.

·       Helps the mother return to the body mass she had before getting pregnant.

·       Breast milk is free and readily available, there is no need to invest in bottles or powdered milk.

·       Reduction in the risk of breast cancer.

A.3.3

Causes:

• Type II diabetes occurs when the body becomes less responsive to insulin due to a down-regulation of insulin receptors in the liver
• Consequently, the body becomes inefficient at lowering blood glucose levels after feeding
• Type II diabetes may be caused by a genetic predisposition, dietary factors (high sugar intake) or a lack of exercise (obesity)

Symptoms:

• High glucose content in blood
• Frequent urination and general thirst
• Tiredness and blurred vision
• Nerve damage and erectile dysfunction
• Kidney and back pain

A.3.4 Explain the dietary advice that should be given to a patient who has developed type II diabetes

       A person who has type II diabetes would be advised to control their calorie intake as well as helping them to maintain a health lifestyle. An obese or overweight patient may be advised to lose weight and do exercise.

Some recommendations may include:

• Maintain a low fat diet in order to avoid gain weight.
• Consume complex carbohydrates to ensure gradual release of glucose into blood
• Eat regular, small meals to ensure a steady supply of glucose into the bloodstream
• Consume “diabetic alternatives” to avoid abrupt changes in blood glucose levels

A.3.5 Discuss the ethical issues concerning the eating of animal products, including honey, eggs, milk and meat

Arguments For:

• Consuming animals or animal products may reduce problems of malnutrition or hunger
• Certain nutrients may only be found in animal products (e.g. vitamin B12 in meat)
• Many jobs may depend on cultivating and preparing animals, leading to an associated increase in unemployment as a consequence.

Arguments Against:

• Using antibiotics to improve the health of livestock may result in antibiotic resistance
• Introducing growth hormones into the animal food supply can lead to side effects or allergies in humans
• Maintaining animals, as a food source requires a significantly larger ecological footprint compared with a plant diet.
• Agricultural practices can lead to the destruction of ecosystems and the loss of biodiversity.
• There can be inhumane treatment associated with animals raised for food (e.g. battery hens)
• Killing animals for meat goes against some religious beliefs (particularly with regards to certain animal species)
• Selective breeding to improve animal yield (e.g bee populations) can threaten the viability of native species

A.3.6 Evaluate the benefits of reducing dietary cholesterol in lowering the risk of coronary heart disease

• Cholesterol is required for cell membrane structure and steroid synthesis, but very little cholesterol comes from the diet.
• High cholesterol diets can lead to atherosclerosis, as characterised by the deposition of fatty plaques and subsequent hardening of the arteries
• However the risks are increased when high levels of saturated fats are combined in the diet.
• High levels of saturated fats also cause atherosclerosis, but also raise levels of LDL (low density lipoprotein) that retains cholesterol in the body.
• Reducing dietary cholesterol levels will likely only be effective in lowering the risk of coronary heart disease if it is combined with lower levels of saturated fats as part of a balanced diet.

  

 A.3.7 Discuss the concept of food miles and the reasons for consumers choosing foods to minimise food miles

• Food miles are a measure of the distance food is transported from the site of production to the consumer
• High food miles cause pollution and greenhouse gas emissions as a result of the increased fuel consumption involved in transport
• High food miles do not support local communities.
• Products with high food miles are less likely to be as fresh as local products and are less likely to contain added preservatives
• Food miles do not take into consideration other environmental costs involved in food production (impact of machinery, pesticides, etc.)