In some countries the average weight of people is increasing and their levels of health and fitness are decreasing.

What do you think are the causes of these problems and what measures could be taken to solve them?

Example 1
Is this a good first paragraph? What is good and bad about it?
In some countries the average weight of people is increasing and their levels of health and fitness are decreasing. This is obviously a bad thing. In the following essay I intend to discuss the causes of these problems and make some suggestions as to the measures that could be taken to solve them.

Example 2
Is this a good paragraph? What is good and bad about it?
In Hong Kong nowadays many people are overweight. Also, Hong Kong people do not do enough exercise. This is because of the long hours that Hong Kong people have to work. However, I think the Hong Kong government should do more to promote a healthier lifestyle.

Example 3
What is wrong with this?
According to recent research the amount of fat that people eat has increased by 50%. This has had an effect on their weight. Also, an article just published in the newspaper shows that people nowadays do only 10% as much exercise as they did 30 years ago.

Example 4
Which of these two paragraphs is better? Why?
Version 1
The food that people eat today is much higher in fat than in the past. Food is relatively cheap these days in comparison to people's earnings. In the old days, people could not afford to buy foods such as meat and dairy products that are high in fat. Nowadays, people can afford to each as much as they like whenever they like.  One reason for the increase in people's weight is their diet.
Version 2
One reason for the increase in people's weight is their diet. The food that people eat today is much higher in fat than in the past. In the old days, people could not afford to buy foods such as meat and dairy products that are high in fat but nowadays many everyday foods contain high levels of these. At the same time, food is relatively cheap these days in comparison to people's earnings, so they can afford to each as much as they like whenever they like. 

Answers	

Example 1
Is this a good first paragraph? What is good and bad about it?
In some countries the average weight of people is increasing and their levels of health and fitness are decreasing. This is obviously a bad thing. In the following essay I intend to discuss the causes of these problems and make some suggestions as to the measures that could be taken to solve them.
The first sentence is copied from the question. The others are unnecessary. They are only restating the instructions.
Example 2
Is this a good paragraph? What is good and bad about it?
In Hong Kong nowadays many people are overweight. Also, Hong Kong people do not do enough exercise. This is because of the long hours that Hong Kong people have to work. However, I think the Hong Kong government should do more to promote a healthier lifestyle.
The question is not specifically about Hong Kong. Feel free to use examples relating to Hong Kong in your writing as this is your personal experience. But avoid giving the impression that you think the question is about Hong Kong.
Example 3
What is wrong with this?
According to recent research the amount of fat that people eat has increased by 50%. This has had an effect on their weight. Also, an article just published in the newspaper shows that people nowadays do only 10% as much exercise as they did 30 years ago.
IELTS essays are written using information you have in your head. They are not researched essays. Do not mention data and sources that do not exist.

Example 4
Which of these two paragraphs is better? Why?
Version 1
The food that people eat today is much higher in fat than in the past. Food is relatively cheap these days in comparison to people's earnings. In the old days, people could not afford to buy foods such as meat and dairy products that are high in fat. Nowadays, people can afford to each as much as they like whenever they like.  One reason for the increase in people's weight is their diet.
Version 2
One reason for the increase in people's weight is their diet. The food that people eat today is much higher in fat than in the past. In the old days, people could not afford to buy foods such as meat and dairy products that are high in fat but nowadays many everyday foods contain high levels of these. At the same time, food is relatively cheap these days in comparison to people's earnings, so they can afford to each as much as they like whenever they like. 
Version 2 is much better. The main idea - one reason for the increase in people's weight is their diet - comes first. This is the topic sentence. The supporting information comes after. This kind of writing is easier to read and understand.