What are the Risks Associated with Having an Underweight or Overweight BMI?

Being either overweight (with higher BMI > 25) or underweight (with lower BMI <20) can affect your health.

Risks of being overweight:

Being overweight increases your chances of developing disease. An overweight individual whose BMI rises from 25 to 27 is 20-30% more at risk of death. As an individuals BMI rises above 27, the risk of death increases more steeply by almost 60%.

If you are overweight and have low physical activity, the risks of developing disease increase. Listed below is a list of disease associated with being overweight.

• Gastrointestinal disorders 
• Cardiovascular diseases i.e. stroke, heart attack 
• Diabetes 
• High blood pressure (Hypertension) 
• Osteoarthritis 
• Infertility
• Some forms of cancer i.e. breast, colon and endometrial cancers 
• Menstrual abnormalities
• Gall bladder disease 
• Sleep problems eg obstructive sleep apnoea 
• Respiratory problems i.e. asthma 

Risks of being underweight:

If you are underweight you may be malnourished and in addition you may develop the following nutritional deficiencies:

• Compromised immune function with increased susceptibility to infections 
• Respiratory diseases 
• Digestive diseases 
• Cancer  
• Osteoporosis (weakening of the bones) 
• Increased risk of falls and fractures