There are many reasons for being underweight, these are some of them: - High metabolism

2. Reasons for being underweight There are many reasons for being underweight, these are some of them: - High metabolism - Skipping meals - eating on the run - illness - injury - active lifestyles - stress - eating food with inefficient nutrition Most of these reasons don’t raise any concerns but illness, stress, skipping meals and insufficient nutrition are all issues.

3. Infertile (Women) Women who are underweight are at risk of being infertile. Infertile means they are not able become pregnant. There are many reasons why they can’t be fertile. - You need to have enough fat to sustain a healthy growing baby. - If you are underweight you cannot ovulate. This means that your body can’t release the egg to be fertilized. - Being underweight can also cause you to miss your monthly cycle. In some cases you may not have a monthly cycle at all. Gaining weight almost always increases chance of pregnancy

4. Osteoporosis Osteoporosis is a common side effect of being underweight. Osteoporosis is a disease that causes your bones to become fragile and easily broken. In most people, their hips, spine and wrist is where their bone is most likely to break. Osteoporosis is caused by: - insufficient calcium, which is needed to strengthen your bones. Due to under eating you don’t get enough of this vitamin - Not getting enough exercise - insufficient vitamin D - alcohol abuse and smoking A balanced diet with plenty of calcium will prevent osteoporosis

5. Anemia Anemia is a health risk of being underweight. This is usually measured by the decrease in haemoglobin (red pigment) in the red blood cells. The red pigment is the oxygen in your blood. This is why used blood is blue, because it is lacking in oxygen. The symptoms of anaemia are: - Fatigue - pain in the chest - shortness of breath If you have anemia you should focus on a weight gain diet

6. Determining if You Are Underweight: BMI BMI stands for Body Mass Index. Doctors use BMI to see if you have an appropriate weight for your height and weight . To calculate your body mass, you divide your weight in pounds by your height in inches squared and then multiply the result by 703 I tested my BMI and found that I was 20.3.

7. Anorexia Anorexia is a mental disorder which deceives the victim into thinking they are overweight. This may lead to them starving themselves. This will cause frequent damage to the heart, liver and kidneys. This may also lead to loss of hair, muscle weakness and joint pain. In some cases the victim starves themselves to death.

8. Bulimia Bulimia is a similar disease to anorexia. People with bulimia have episodes of significant overeating and feel out of control. The victim then vomits their food out to prevent further weight gain. This may cause damage to the damage to the stomach, teeth, throat, and brain. This can also lead to death.

9. Bibliography http://weightgain.lifetips.com/cat/61224/health-risks-of-being-underweight/index.html http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001381/