Human beings are a body of energy that continuously need fueling. In comparison to machines, abnormally frequent fueling is very dangerous because our human body processes every “fuel” available at an instance. A good friend once said, “the physiological ambience is a closed system full of multiple interactive factors” as he described the complexity and the intertwined interdependence of our human body system.
The American Medical Association (AMA) classified obesity as a disease in 2013. The AMA defines obesity as a chronic disorder as a result of the expansion of fat deposits in the body. Overweight and Obesity usually walk parallel to each other. Body mass index (BMI) is a simple index for calculating body fat in adults. The BMI is derived from a person’s weight in kilograms divided by a square of the height of the person in meters. BMI greater than or equal to 25 indicates an overweight person whiles a BMI greater than or equal to 30 indicates obesity.
Very commonly, obesity is associated with an unhealthy lifestyle of excessive eating without exercise. About 10% of all cancer deaths among non-smokers are related to obesity recalled by Professor Philip James. The Centers for Disease Control and Prevention estimated that between 2015 and 2016, about 93.3 million (40%) adults and about 13.7 million (18.5%) children in the United States were obese. Obesity tends to decrease lifespan and increase one’s risk of acquiring some endocrine or cardiovascular problems grouped as Metabolic syndrome. Metabolic syndrome is diagnosed by the evidence of at least three out of five of the following:
- High blood pressure
- High serum triglycerides (increased fatty acid and glycerol)
- Low serum high-density lipoproteins (decreased amount of good cholesterol)
- Central Obesity (abnormal fat around the stomach and abdomen)
- High blood sugar
Obesity by The World Health Organization
The world health organization indicates that the fundamental cause of obesity is an imbalance between calories consumed and calories expended. A calorie is a unit of energy for the food one consumes. Excess of calories from proteins, carbohydrates and fats stored within tissues accumulating to increase body weight and energy. The WHO links the emergence of obesity to two factors namely;
- The increase in consumption of food high in calories like fatty foods or junk.
- The decreased in physical activity worldwide due to changing modes of transport and increasing urbanization.
In 2004, The WHO adopted the “WHO Global Strategy on Diet, Physical Activity and Health”. This strategy is implemented worldwide to support the need for healthy dieting and encouraging regular exercise. This implementation is supposed to help decrease the “double burden” of disease within low- and middle-income countries. It is no news that people in these countries suffer alarming rates of infectious diseases. An additional upsurge of noncommunicable diseases due to the risky conditions associated with overweight and obesity indicates a “double burden” of disease.
TYPES OF OBESITY
Obesity can be divided into hypertrophic or hypercellular (hyperplastic) based on histologic (microscopic tissue study) appearance. Hypertrophic obesity is characterized by an increase in adipose cell size resulting from an increase in fat storage, usually onset in adults. Hypercellular obesity is characterized by an expansion in the number of adipose cells. This type begins in childhood and is often lifelong.
Calorie as already described is the energy that burns for the body to do work. If more calories are taken in than one works, these calories accumulate as fat and increase one’s weight. Similar if more calories are burnt than one replenishes, weight loss is the outcome. 1 calorie from food may be defined as the amount of energy it will take to raise a 1kg mass of water by 1-degree Celsius. This is actually the number of energies stored in the chemical bonds of the food molecules. For example, there are about 78 calories in a slice of bread and about 272 calories in a pizza slice. Also, a gram of fat in food contains 9 calories, and a gram of either protein or carbohydrate contains about 4 calories. Digestion uses about 10% of caloric intake, physical activities make use of about 20% and about 70% is used for basic bodily functions (metabolism).
The use of calories for body functions is associated with metabolism (basal metabolic rate). The basal metabolic rate is the amount of energy each person burns out per unit time when the body is at rest. The BMR affects how much calories are burnt in the body which influences how individuals gain, loses or maintains their weight. BMR is dependent on normal body processes like breathing, blood circulation, homeostasis (body temperature control), growth, neural activity and muscle activities. Therefore, an increase in BMR increases weight loss and vice versa.
Body chemicals (adipokines and cytokines) that control Obesity.
- Leptin hormone– The genetic association of obesity is usually due to a faulty gene coding the hormone leptin or the leptin receptor. A decreased sensitivity to leptin decreases the ability to induce satiety, this mimics the effect of insulin-resistant type 2 diabetes mellites. Leptin is known as the hormone of energy expenditure or the satiety hormone. It is released by white adipose cells to inhibit hunger. Leptin activity opposes ghrelin whose activity increases hunger and prepares the stomach and bowels for incoming food. Due to an increased number and size adipose cells in obese individuals, serum leptin levels are about 7 times greater than in thin or normal individuals.
- Adiponectin– This is a peptide hormone secreted from adipose tissue that tends to increase insulin sensitivity, increases glucose uptake from the blood, decreases gluconeogenesis (formation of new glucose molecules from non-carbohydrate carbon substances), inhibits glucose release from liver cells and regulates fatty acid oxidation (breakdown to energy substrates). Adiponectin increase weight loss. Blood levels of adiponectin are greater in thin individuals than in obese people.
- Resistin– This is another peptide hormone produced by adipose tissue. Studies have shown that resistin increases the level of low-density lipo-proteins (bad cholesterol) in the blood. This poses a risk for acquiring atherosclerosis which leads to heart diseases and stroke. Resistin promotes insulin resistance which leads to hypercalcemia and Type 2 DM.
- Irisin– Skeletal muscles tend to release this hormone in response to aerobic endurance activity so it’s often called the “exercise hormone”. Irisin has the potential of generating weight loss and decreasing the development of diabetes.
- Cytokines– There have been many reports that obesity is always accompanied by Chronic inflammation. This inflammatory reaction calls on inflammatory agents like macrophages that invade these adipose tissues. The two main cytokines produced by these macrophages are as follows;
- TNF-alpha increases insulin resistance and represses the liver’s ability to oxidize (breakdown) fatty acids into energy substrates.
- IL-6 is an important regulator of acute phase reactants (proteins in the blood that increases when systemic inflammation occurs). The action of IL-6 is similar to TNF-alpha but it increases skeletal muscle glucose uptake and ability to oxidize (break down) fatty acid into energy substrates.
There has always been a constant need to keep up education and reminders of healthy living but to speak for both sides, healthy living does not come easy. It is essentially a whole new lifestyle change for anyone trying to make it, and like Josh Billings once said, “there are a lot of people in this world who spend so much time watching their health that they haven’t had time to enjoy their health”, it is equally relevant that we appreciate and enjoy the sound health that we strive so much to attain.
LIST OF COMMON CONDITIONS ASSOCIATED WITH OBESITY
- High blood pressure
- Diabetes mellitus
- Dyslipidemia (abnormal cholesterol and triglycerides)
- Coronary Heart Disease
- Gallbladder disease
- Mental illness (Depression, Anxiety)
- Osteoarthritis (bone cartilage problems)
- Gout (swollen and painful joints)
- Sleep Apnea
- Cancers (breast, gall bladder, colon, prostate)