“And put a knife to thy throat, if thou be a man given to appetite.” Proverbs 23:2

Understanding how and why obesity develops is incomplete, but studies show it involves a combination of social, behavioural, cultural, physiological, metabolic and genetic factors. What we do know is that obesity has a significant impact on the person in many different ways. We continue this month, discussing the negative effects that obesity has on one’s health.

RESPIRATORY DISEASES

People with obesity have reduced lung capacity. Excess body fat prevents full expansion of the lungs. Because of this, obesity can contribute to a higher risk of respiratory infections. This is due to the fact that individuals are unable to clear potential infections from the lungs as readily when breathing. They are also more likely to have asthma and other respiratory disorders. Asthma has been shown to be three to four times more common among people with obesity. The increase in asthma with obesity is due to several factors. Overall body inflammation, which contributes to the risk of developing asthma or worsening of existing asthma, is increased with obesity. Being overweight can affect lung function; people have reduced lung volumes and elasticity due to the narrowing of the airways, which can cause them to close during normal breathing. Also, obesity can change blood volume within lung tissue, impacting the efficiency of oxygen exchange. Increased body fat can compress the lungs and actually infiltrate lung tissue, increasing blood volume and decreasing the diameter of airways. All these changes lead to an increased difficulty in breathing, and can limit airflow in the lungs. Finally, there are specific genes that are related to both asthma and obesity, therefore there is a genetic component that links these two conditions. Weight loss in obese individuals can alleviate 48%–100% of asthma symptoms.

Obstructive sleep apnea (OSA) is a very serious breathing disorder. More than half of those who are obese have OSA. This condition occurs when excess fat in the neck, throat and tongue block the air passageways when someone lies down, typically during sleep. This blockage causes apnea, which is when someone temporarily and repeatedly stops breathing for a few seconds to a few minutes at a time. A person with OSA may have up to hundreds of episodes of apnea during a night of sleep. One symptom of OSA is excessive snoring. During an episode of apnea, a person must wake up, even very briefly, to start breathing again. This disrupts the regular sleep cycle, and thus people with OSA do not tend to get a restful night’s sleep, and often suffer from daytime fatigue. OSA can lead to even more serious cardiovascular complications such as high blood pressure, high pressure in the lungs, decreased oxygen in the blood, irregular heart rhythms, and increased risk of heart attacks and strokes. Standard treatments for sleep apnea will reduce rcardiovascular risks.

CANCER

Cancer affects more than half a million lives per year in the United States alone. Obesity is believed to cause up to 90,000 cancer deaths per year. In 2012 in the United States, about 28,000 new cases of cancer in men (3.5%) and 72,000 in women (9.5%) were due to overweight or obesity. Some cancers are more strongly linked to obesity. As body mass index (BMI) increases, so does your risk of cancer and death from cancer. These cancers include: Endometrial cancer; Cervical cancer; Ovarian cancer; Post-menopausal breast cancer; Colorectal cancer; Esophageal cancer; Pancreatic cancer; Liver cancer; Kidney cancer; Thyroid cancer; Prostate cancer; Non-Hodgkin’s lymphoma; Multiple myeloma; Gallbladder cancer; Leukemia.

Even comparing normal weight and obese people who have developed cancer, for people with severe obesity, the death rate increases for all types of cancer. With obese persons, the death rate is 52 percent higher for men and 62 percent higher for women than for those of normal weight.

Why does obesity increase the risk of cancer? Obese people often have chronic low-level inflammation, which can, over time, cause DNA damage that leads to cancer. They have conditions or disorders that are linked to or cause chronic inflammation which are risks for specific cancers. Fat tissue produces excess amounts of estrogen, high levels of which have been associated with increased risks of breast, endometrial, ovarian, and some other cancers in women. Obese individuals often have increased blood levels of insulin, which promote the development of colon, kidney, prostate, and endometrial cancers. Fat cells produce hormones that may stimulate cell growth, including the increased growth of cancer cells. Obesity also alters a person’s immune response, making it less effective in fighting cancer cells; it also causes a decrease in levels of antioxidants in the body. This then produces more free-radicals that can damage cells in the body, making them cancerous.

Many studies have found a positive relation between obesity and colon cancer. This is one cancer that occurs with a higher waist-to-hip ratio, than with an elevated BMI alone. Even among normal-weight people, a high waist-to-hip ratio is also associated with significantly increased risk of colon polyps, which often lead to cancer.

Breast cancer studies consistently show that obesity is directly related to death from breast cancer, predominantly in postmenopausal women. Interestingly, obesity decreases risk of breast cancer in premenopausal women. However, ten or more years after menopause, the premenopausal “benefit” of obesity disappears. Among postmenopausal women, peripheral fat is the primary source of estrogens, which is a major risk factor for postmenopausal breast cancer. A gain of more than 9 kg (20 lbs) from age 18 to midlife doubles a woman’s risk of breast cancer. Even modest weight gains are related to increased risk of postmenopausal breast cancer.

FERTILITY ISSUES

Women who are overweight or obese have less chance of getting pregnant overall. They are also more likely than women of healthy weight to take more than a year to get pregnant. Obesity can affect fertility by causing hormonal imbalances and problems with ovulation (ovaries ability to produce eggs), particularly for obese women having their first baby.

Obesity also increases a woman’s risk of developing a condition called polycystic ovary syndrome (PCOS), which is considered a leading cause of infertility. Obesity in women is associated with menstrual irregularity and amenorrhea (lack of menstruation), which affects normal ovulation. The greater the BMI at age 18 years, even at levels lower than those considered obese, the greater the risk of subsequent infertility when women try to conceive.

PREGNANCY COMPLICATIONS

Pregnancy complications can occur with any pregnant woman, independent of weight. However, obesity increases the risk of complications for pregnant women and their babies. The higher a woman’s BMI, the higher the risks. In women considering having a child, maintaining a normal weight is ideal in having a healthy pregnancy. However, if you are obese and pregnant, it may not be safe try to lose weight during your pregnancy. There is no evidence that losing weight while you are pregnant will reduce the risks.

A complication which occurs in higher incidence in obesity is miscarriages. The risk is doubled, and can be as high as 25%. Developing diabetes during pregnancy is three times more likely than in women whose BMI is below 30. This is known as gestational diabetes. Blood sugars will need to be monitored throughout the pregnancy to prevent complications for the baby, which may include excessive birth weight, early labour, and respiratory distress syndrome (difficulty breathing).

High blood pressure and specifically pre-eclampsia, which is high blood pressure combined with other complications is the leading cause of death to both mother and baby. Women with pre-eclampsia are at increased risk for damage to other organs, with the highest risk of kidney and liver damage. Pre-eclampsia may also affect the placenta. The condition could lead to a separation of the placenta from the uterus, preterm birth, or stillbirth. In some cases, pre-eclampsia can lead to organ failure or stroke. In severe cases, pre-eclampsia can develop into eclampsia, which includes seizures. If the fetus is not delivered, these conditions can cause the death of the mother and/or the fetus. If one has a BMI of 35 or above at the beginning of the pregnancy, the risk of pre-eclampsia is twice that of women who have a BMI under 25. Expectant mothers rarely die from pre-eclampsia in the developed world if they are being followed by a doctor during pregnancy, but it is still a major cause of illness and death globally. According to the World Health Organization, pre-eclampsia and eclampsia cause 14% of maternal deaths each year, or about 50,000 to 75,000 women worldwide.

All pregnant women have a higher risk of developing blood clots compared to women who are not pregnant; with obesity the risk is even higher. Obese mothers also have larger babies. Any baby weighing more than 4 kg can lead to the need for early delivery. Premature babies can have breathing issues. Because of these large babies, obese women are more likely to require a forceps delivery or an emergency caesarean section to give birth. One of the baby’s shoulders can become stuck behind the mother’s pubic bone during delivery, delaying the birth of the baby’s body. If this happens, extra help is usually needed to release the baby’s shoulder. Post-partum hemorrhage can occur, which is heavier than normal bleeding after birth. There is also a greater likelihood that a woman will go into labour early; often a

baby will be born early (before 37 weeks). There is also an increased risk of stillbirth in obese women. Congenital abnormalities in babies born to obese women are also higher than in normal weight women. Babies born to overweight or obese mothers are more likely than those born to healthy-weight mothers to become obese children and adults, and to have more health problems, including diabetes.

OTHER PHYSICAL CONDITIONS

As well as the health effects of obesity that have been mentioned over the last three articles, several other conditions are worth mentioning. Some of these conditions are as a result of the other health effects mentioned already. Obesity, especially in middle-age, with other health effects, contribute to the increased risk of dementia and Alzheimer’s disease later in life. Kidney disease and kidney failure have high blood pressure, diabetes, and heart failure as contributing factors. Septicemia, a serious blood infection that can often be fatal, is higher in people with obesity. This is related to an overall less effective immune system. Obesity is also a major cause of fatty liver disease, which can cause scarring of the liver, leading to worsened liver function, cirrhosis and liver failure. Obesity has been associated with a higher risk of Gastroesophageal Reflux Disease (GERD), which causes stomach acid to leak into your esophagus, causing symptoms such a heartburn and indigestion. Increasingly, many of the diseases, previously associated only with adulthood, are also being seen in overweight and obese children.

PSYCHOLOGICAL DISORDERS 

Obesity is not just an epidemic that is hazardous to one’s physical health, with all the risks for life-shortening chronic diseases. Being obese also has an impact on the mental, emotional and social aspects of one’s life. People who are obese have a greater risk of depression and anxiety. They also suffer from low self-esteem, and avoid interactions with other people because of their weight. Women especially, who are more conscious of their personal appearance than men, can lead to developing eating disorders such as anorexia so that they can slim down. Adults who were obese as children appear to have an increased risk of psychological problems.

The reason for the impact on one’s mental health are the negative attitudes about obesity that are prevalent in society, in children, adults, with health care professionals, and in the overweight people themselves. In Western society, being overweight is stigmatized, with people who are obese considered as having a lack of self-control, being lazy, and gluttonous. Because of this, people who are obese are discriminated against in various situations. In employment, issues include finding and obtaining a job. Certain jobs whereby a certain “image” is needed in order perform well are given to those who are considered physically attractive. This can discriminate against those who are obese, as they are considered less appealing and would be less effective in their jobs. These include jobs that have face-to-face contact with those who an employer relies on for income and profit.  Other areas of discrimination are in education, health care, schooling, housing, and relationships.  Stigma can reduce the quality of care for patients with obesity despite the best intentions of healthcare providers to provide high-quality care, and often doctors avoid having discussions with their patients in helping them to reduce weight. In children, overweight and obesity has also been linked with poor concentration levels, poor academic success and social exclusion in school.

The social aspect of weight gain has been shown in a number of studies. In groups of people who are close friends, when one person gains weight their close friends also gain weight. Friends are the biggest influence when it comes to weight gain and if a friend became over weight you had a 57 percent higher chance of becoming obese; if it was a close mutual friend your chances rose to 171 percent. One changes their idea of what is an acceptable body type by looking at the people around them. Because of this influence, the amount of people who are obese is growing because of others around them who are obese.

As we have seen over these last three months, there exists many negative effects on an individual’s health and wellbeing with obesity; however, there is a solution. It is a condition that people can do something about. Many of the risk factors for obesity are modifiable, within an individual’s control. For example, by reducing body weight by just 5-10%, health risks are dramatically reduced. Losing weight also means levels of activity can be increased—contributing towards further weight loss. We will look at ways that an individual, and society as a whole, can help reduce the impact that obesity has on the world’s population next month.

“In nine cases out of ten there is more danger of eating too much than too little. . . . There are many sick who suffer from no disease. The cause of their sickness is indulgence of appetite. They think that if the food is healthful, they may eat as much as they please. This is a great mistake. Persons whose powers are debilitated should eat a moderate and even limited amount of food. The system will then be enabled to do its work easily and well, and a great deal of suffering will be saved.” –Child Guidance, p. 399

NEXT MONTH: SOLVING THE OBESITY EPIDEMIC