Nutrition

Vocabulary_Nutrition.pdf

Track your food for 48h!

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Questions

Imagine a day in the life of Josh. What does he eat for breakfast, lunch and dinner?
How long has Josh been eating just Pizza?
Why does Josh want to change what he is eating?
Why would a doctor say that Josh's Pizza only diet is unhealthy?
Malnutrition can be caused by too little or too much of a nutrient. What is it missing, what is too much?

Imagine that Josh eats 10 slices of pizza's per day. Which nutrients will he be lacking, which will he have too much of?

Look up the nutritional value of pizza using this the pizza nutritional analysis worksheet shown aside ---->

Is it nutritious?

https://www.food-nutrients-calculator.com/

A particularly nice option is the Food Comparator where two foods can be compared side by side.

Cheese Pizza (standard portion - 140g)
Cream of Vegetable soup (standard portion - 250ml)

is_it_so_bad_to_eat_only_pizza.pdf

Hopefully you eat a more balanced diet than Josh. Test your fruit and vegetable consumption using this online nutrition screener from Nutrition quest

Pizza could be quite a good source of nutrients if it is made from whole wheat flour, fresh tomatoes, with a range of meat and vegetables in the topping and not too much cheese. So why is it so bad to eat just Pizza? Of course most fast food pizza is not made from fresh ingredients and often contains high levels of cholesterol, and salt.

Micronutrients - Hidden hunger

'Hidden hunger' is when people get enough food, but their food is missing some essential nutrient, like a vitamin or mineral. Having too much or too little of a nutrient is called malnutrition. This graphic Micronutrients infographic from https://www.uea.ac.uk/ shows some of the main causes.

Questions

1. Which vitamin and which mineral is most lacking in the diets of children in poor countries of the world?

2. What is the effect on the body of a diet with a lack of the following essential nutrients;

Vitamin A: ............................................................
Iodine ..................................................................
Calcium ........................................... ...................

3. Which of the nutrients above are minerals? Explain why.

Micronutrients.pdf

Model answers here.

Micronutrient difficiency around the world: there is a super Canadian organisation doing great work improving childrens' health in many countries using food suppliments

This video Scaling up nutrition a short video shows some of the activities undertaken by micronutrient inititative and it's partners around the world.

Control of appetite

The hypothalamus in the brain plays a key role in the control of appetite. The hormones PYY, insulin and leptin reduce appetite.

Read about several interesting cases, including PKU, obesity and anorexia and answer some self marking multiple choice questions to test your understanding.

1 What is energy homeostasis?

2 Which part of the brain receives signals from fat cells and the intestines to signal that you are hungry?

3 What is the role of leptin on appetite? (Remember HL topic 11?)

Find this fascinating? If you are keen to find out more try this A more detailed introduction to the science of nutrition

Malnutrition and unusual cases.

Case 1 - PKU

While for most of us eating a diet containing all the essential micronutrient is essential, some people need to eat a diet which is missing an essential amino acid - "Phe" or phenylalanine. (pronounced FEE - NYE - ALA - NYNE).

This is an inherited condition where person has two faulty alleles of the gene for the enzyme which hydrolyses this amino acid.

Watch the following video about PKU.

Answers here.

Case 2 - Vitamin C - is it really an essential vitamin?

Read the two short articles below and answer the question which follows.

Ascorbic Acid (Vitamin C) for Dogs and Cats Dr. Nicholas Dodman Last Modified: July 09, 2015

Ascorbic acid, also called Vitamin C, is a naturally occurring substance that is important in the formation of collagen in dogs and cats. Ascorbic acid is manufactured by most animals, except for some birds, fish, guinea pigs, fruit bats, primates and humans.

In dogs and cats, ascorbic acid is manufactured in the liver and normally does not need to be supplemented. Claims that nutritional deficiency of ascorbic acid causes scurvy in dogs and cats are probably inaccurate. The only situation in which ascorbic acid deficiency might occur in dogs and cats is in the case of liver disease, which might disrupt its production.

Ascorbic acid is available over-the-counter but should not be given to cats and dogs except under the supervision of a vet.

Vitamin C and Guinea pigs - by Pete and Guinea pig Corner

Like chickens, humans and other mammals, guinea pigs need vitamin C to keep their bodies functioning properly. Also like humans, but unlike other rodents and other animals, guinea pigs are unable to produce their own supplies of vitamin C. This means that they must get 100% of their requirements from the food and supplements you feed them.

Problems Caused by Vitamin C Deficiency

When guinea pigs don't have enough vitamin C in their diets, it can lead to a number of diseases and ailments.

Answers here.