Tag Archives: health

STEM Students answer Children’s Questions #4

When visiting schools and museums our Street Scientists often get asked a variety of questions from curious children. Here are the answers to some of our favourite questions!

This week, we’re answering questions around Medicine and Health.

What is blood made of?

-asked by Lacey, 8, from Simonside Primary School

There are many things which make up blood! The easiest way to think about it is that it contains liquids and solids. The liquid part of blood is called plasma which is mainly water with some salts dissolved in it and also some proteins. The plasma allows blood to flow, carrying the solids around the body to where they are needed. The salts are important in controlling how much water is in the body, this is why it is dangerous to eat lots of salt!

The plasma makes up around half of blood, the rest is made up of red blood cells, white blood cells and platelets. Red blood cells have a dip in the middle which gives them lots of space to carry oxygen from the lungs to the body. Oxygen bound to red blood cells is what makes blood red.

The white blood cells come in lots of different types and are part of the immune system which protects the body from germs like bacteria and viruses. They recognise germs which don’t belong in the body and kill them in lots of different ways before they can make us sick.

Platelets are important in allowing us to form scabs when we cut ourselves. The platelets all stick together over a cut and stop us losing too much blood. 
-Ailie, Medical Student & Evolution and Human Behaviour Masters Student

Why do people get allergic reactions to things?

-asked by Abbie, 11, Burnside Primary School

Allergic reactions happen in some people when the immune system overreacts to something harmless, called an allergen, because it thinks it is dangerous to the body. Our immune system is very important to keep our bodies safe from germs such as bacteria and viruses that can cause disease. While the red cells in our blood carry oxygen all around the body, the white blood cells make up the immune system.

The white blood cells are very clever at recognising germs in the body and realising that they don’t belong and can be harmful. When they find a germ, they activate other white blood cells to attack the germ in lots of different ways. Some white blood cells can swallow a germ whole and then dissolve it – this is called phagocytosis. Other white blood cells release antibodies which stop the germs being harmful and cause them to all stick together, others release chemicals such as histamine which causes swelling and brings in more white blood cells to help.

However, in some people the white blood cells get confused and think something safe, like peanuts or shellfish, are harmful to the body. Scientists haven’t figured out why this happens to some people but not others although sometimes it runs in families and is linked to other conditions like asthma and hay-fever. When people with allergies eat or touch something they are allergic to the immune system becomes activated causing redness, swelling and itching. In a serious case the throat may swell up making it hard to breathe, this is why some people with allergies carry an EpiPen which contains adrenaline to stop the swelling.
-Ailie, Medical Student & Evolution and Human Behaviour Masters Student

How many medicines are in the world?

-Asked by Ruby, 10, from Simonside Primary School

It is impossible to know exactly how many different medicines there are, it will be thousands and thousands! The types of medicines used in different parts of the world are very varied and medicines are always changing.

Doctors used to think that all sickness was due to ‘bad blood’ so they put leaches on sick people to suck it out! Luckily, they don’t do that anymore. For most diseases there are many treatments available. For example, there are lots of different inhalers for asthma which are different colours depending on which medicine is inside, and there are tablets you can take too. Which medicine works best depends on the person, sometimes doctors have to try a few before they find the right one. Medicines come in lots of different forms, sometimes you may take an antibiotic as a pill, drink it as a liquid, or have it as an injection.

In summary, there are too many medicines to count! Some things we use every day such as garlic and ginger can be used as medicine if you know what you are doing! Luckily for everyone Scientists and researchers are creating more medicine and treatments every day!
-Ailie, Medical Student & Evolution and Human Behaviour Masters Student

I would like to work in Tropical Medicine. How long would I need to study for?

-asked by Liam, 11, Burnside Primary School

Lots of people work in tropical medicine including biomedical researchers, epidemiologists, doctors and microbiologists to name a few. So the length of time you have to study for will really depend on what aspect of tropical medicine you want to end up in, most researchers for example will have done 4 or 5 years of university and doctors need to have done 5 years of university and 9 years of specialist training. People who work in tropical medicine are always learning new things even after they’ve officially stopped studying.
-JC, Medical Student

World Health Day – the Eatwell Plate

To celebrate World Health Day, we have a guest post from Jenny, a Dentistry Student at Newcastle University

Eatwell plate

This is the Eatwell Plate. It is a handy visual guide showing exactly how much each food group should contribute to what we eat on a daily basis to maintain a healthy and balanced diet.

The plate is divided into the 5 main food groups we should consume every day:

  1. Fruit and vegetables – 40% of what you eat in a day.
  2. Pasta, potatoes, rice, bread and other starchy carbohydrates – 38% of daily food intake.
  3. Protein sources such as beans, eggs, meat, pulses and fish – 12% of daily food intake.
  4. Milk and dairy (including dairy alternatives) – 8% of daily food intake.
  5. Oils and spreads – 1% of daily food intake.

You may have noticed that these percentages only add up to 99%. This is because the final 1% is allocated for high fat, salt and sugar foods such as fizzy drinks or chocolate bars. These food stuffs should rarely be consumed and only in small amounts.

As well as that, we should be drinking 6-8 glasses of fluids every day. This includes water, low fat and low sugar milk, and fruit juice that is not from concentrate.

The balance displayed on the Eatwell Plate does not have to be achieved in every meal of the day but should be attained for what you eat overall in a day. With that said, let’s take a more in depth look at the food groups.

Fruit and vegetables

You should always try to eat 5 portions of fruit and vegetables a day and familiarise yourself with how much of each fruit or vegetable contribute to one portion (e.g. 7 strawberries = 1 portion). This can be in the form of fresh, frozen, tinned or juiced fruit (although juiced or fruit smoothies should be limited to 150ml/day because they have higher sugar content than fresh fruit). Fruit and veg is a vital part of maintaining a healthy lifestyle because they contain a variety of vital minerals, vitamins and nutrients. For example, broccoli, spinach and lots of other green vegetables are excellent sources of vitamin C, great for maintaining strong bones, joints and to boost your immune system. Also, parsnips, Brussels sprouts and bananas are great sources of potassium, which helps to maintain healthy heart muscles.

Pasta, potatoes, rice, bread and other starchy carbohydrates

Every meal should be built on a starchy carbohydrate base, with wholegrain versions of pasta, rice and bread chosen when possible. Starchy carbohydrates are a very important source of energy because our bodies break down carbohydrates into sugars which are then converted into energy. They are also a source of calcium, iron, vitamin B and fibre, which aids digestion.


Protein is very important in building muscle strength and facilitating growth and repair in our bodies. To achieve correct protein intake, each week you should have two portions of fish, including one portion of oily fish, such as salmon or mackerel. This is because oily fish provides out bodies with the fatty acid, omega-3 and vitamin D, which help maintain a healthy heart.

Protein from red meats should be limited to less than 70g per day because high consumption of red and processed meats could increase risk of developing cancer in older individuals. However, red meats are an excellent source of iron which increases our blood’s ability to transport oxygen allowing us to be more active.

Milk and dairy

Dairy products and dairy alternatives (such as soya, oat or almond milk) are excellent sources of calcium which helps maintain strong bones and teeth. Dairy products include cheese, milk and yoghurt, although you should always pick products which are low in fat and sugar.

Oils and spreads

When it comes to choosing what to put on your toast in the morning, it is always better to use a spread that contains unsaturated fats, such as vegetable, olive and sunflower oils. The same applies to cooking oils. Unsaturated fats help protect our hearts and reduce cholesterol. Food stuffs with high fat content should be rarely consumed.

Finally, a few handy tips for a healthy and balanced meal:

  1. Everything in moderation – eating the recommended portions of each food group outlined by the Eatwell plate, will ensure you get all the vital daily vitamins, nutrients and minerals you need. Cutting out whole food groups (like carbohydrates) rather than improve your health will actually result in poor health effects such as tiredness and stomach upsets.
  2. Make your plate every colour of the rainbow – if your meal looks too beige or too much of one colour, you won’t be getting all the necessary micronutrients you need.

In the spirit of World Health Day, why don’t you take the opportunity to maintain a healthy, balanced diet and make your plate and Eatwell Plate.