Many of the causes of overweight and obesity are preventable and reversable. However, no country has yet to reverse the growth of this epidemic. Although other factors are involved, the fundamental cause of obesity is an imbalance of calories consumed and calories expended. As global diets have changed in recent decades, there has been an increase in the consumption of energy-dense foods high in fat and free sugars. There has also been a decrease in physical activity due to the changing nature of many types of work, more access to transportation and increased urbanization.

Overweight and obesity are major risk factors for a number of chronic diseases, including cardiovascular diseases such as heart disease and stroke, which are the leading causes of death worldwide. Being overweight can also lead to diabetes and its associated conditions, including blindness, limb amputations, and the need for dialysis. Rates of diabetes have quadrupled since around the world since 1980. Carrying excess weight can lead to musculoskeletal disorders including osteoarthritis.

Human immunodeficiency virus (HIV) is an infection that attacks the body’s immune system, specifically the white blood cells called CD4 cells. HIV destroys these CD4 cells, weakening a person’s immunity against infections such as tuberculosis and some cancers.

WHO recommends that every person who may be at risk of HIV should access testing. People diagnosed with HIV should be offered and linked to antiretroviral treatment as soon as possible following diagnosis. If taken consistently, this treatment also prevents HIV transmission to others.

Safe and effective vaccines are available to prevent hepatitis B virus (HBV). This vaccine also prevents the development of hepatitis D virus (HDV) and given at birth strongly reduces transmission risk from mother to child. Chronic hepatitis B infection can be treated with antiviral agents. Treatment can slow the progression of cirrhosis, reduce incidence of liver cancer and improve long term survival. Only a proportion of people with chronic hepatitis B infection will require treatment.

Working4Health

The Working for Health Programme is a joint WHO, ILO and OECD programme to expand and transform the health and social workforce to drive inclusive economic growth and achieve the Sustainable Development Goals. 
 

Chemicals are part of our daily life. All living and inanimate matter is made up of chemicals and virtually every manufactured product involves the use of chemicals. Many chemicals can, when properly used, significantly contribute to the improvement of our quality of life, health and well-being. But other chemicals are highly hazardous and can negatively affect our health and environment when improperly managed. 

There is no specific antiviral drug treatment for chikungunya and there is no commercial chikungunya vaccine. Treatment is directed primarily at relieving the symptoms, including joint pain. This is largely achieved by using anti-pyretic drugs to reduce fever, by optimising the use of pain medication and by administering fluids. Aspirin and other non-steroidal anti-inflammatory drugs should not be administered until dengue can be ruled out in order to reduce the risk of bleeding.  

Vast disparities exist around the world in a child’s chances of survival, with low- and middle-income countries disproportionately affected. Sub-Saharan Africa has the highest child mortality rate in the world, in some places 15 times higher than in high-income countries. The leading causes of death among children include respiratory infections, diarrhoeal diseases, measles, malaria, malnutrition and newborn conditions. Many child deaths are preventable through vaccination, adequate home care, access to health care services, improved rates of breastfeeding and better nutrition.

from diarrhoea, 270 000 deaths from neonatal conditions, 200 000 deaths from malaria and 200 000 deaths from unintentional injuries.

Environmental risks have an impact on the health and development of children, from conception through childhood and adolescence and also into adulthood. The environment determines a child’s future: early life exposures impact on adult health as fetal programming and early growth may be altered by environmental risk factors.

Climate change is impacting human lives and health in a variety of ways. It threatens the essential ingredients of good health - clean air, safe drinking water, nutritious food supply, and safe shelter - and has the potential to undermine decades of progress in global health.

Between 2030 and 2050, climate change is expected to cause approximately 250 000 additional deaths per year, from malnutrition, malaria, diarrhoea and heat stress alone. The direct damage costs to health is estimated to be between USD 2-4 billion per year by 2030.

WHO recommends that infants start receiving complementary foods at 6 months of age in addition to breast milk. Initially, they should receive complementary foods 2–3 times a day between 6–8 months and increase to 3–4 times daily between 9–11 months and 12–24 months. Additional nutritious snacks should also be offered 1–2 times per day for ages 12–24 months, as desired. 

Approximately 50% of congenital anomalies cannot be linked to a specific cause. However, known causes include single gene defects, chromosomal disorders, multifactorial inheritance, environmental teratogens and micronutrient deficiencies. Genetic causes can be traced to inherited genes or from mutations. Consanguinity – when parents are related by blood – increases the risk of congenital anomalies and nearly doubles the risk of neonatal and early childhood death, intellectual disability and other health conditions.

There are many different types of contraception, with varying rates of effectiveness depending on correct usage. Some methods may be obtained over the counter, others may require medical advice or even surgical intervention. 

Health care providers play an important role in helping people find and use a method that is both effective and acceptable. Methods include:

Hormonal contraceptive methods 

Usually oral pills or implants, patches or vaginal rings. They release small amounts of one or more hormones which prevent ovulation. 

It is important that family planning is widely available and easily accessible through trained health workers to anyone who is sexually active, including adolescents.