In a kinder environment that is contributed by studies done by scholars, obesity is no longer looked upon as sorely caused by overeating behavior and lifestyle. Other factors such as genetics, hormones, food addiction to engineered junk foods, Western Pattern Diet (WPD) that promotes Insulin resistance, medications, Leptin resistance and the insidious prevalence of sugar in foods also come into play. Certain people are simply predisposed to gaining weight.
Genetics — Some people are predisposed to obesity as it has a strong genetic component. Having family history of obesity increases the odds, for example children of obese parents are much more likely to become obese than children of normal weight class parents, although it is not completely predetermined. What you eat can have a major effect as well, on which genes are expressed and which are not. Unhealthy diet consumption may change the environment and the signals sent to the genes, which can affect your susceptibility to gaining weight. Studies on identical twins demonstrate this very well.
Food addiction to engineered junk foods — Many sugar-sweetened, high-fat junk foods stimulate the reward centers in your brain, which can cause addiction in susceptible individuals. You eat more as you lose control over your eating behavior, similar to people struggling with alcohol addiction losing control over their drinking behavior.
Western Pattern Diet that promotes Insulin resistance — Elevated insulin levels caused energy to get stored in fat cells instead of being available for use. While insulin’s role in obesity is controversial, several studies suggest that high insulin levels have a causal role in the development of obesity.
The Western pattern diet (WPD) is defined as “a modern dietary pattern that is generally characterized by high intakes of red meat, processed meat, pre-packaged foods, butter, fried foods, high-fat dairy products, eggs, refined grains, potatoes, corn (and high-fructose corn syrup) and high-sugar drinks”.
Medications — Certain pharmaceutical drugs can cause weight gain as a side effect, such as antidiabetic medications, antidepressants, antipsychotic drugs, stimulant drugs for children suffering from hyperactivity. These drugs alter the function of your body and brain, reducing metabolic rate or increasing appetite.
Leptin resistance — Leptin is a hormone that plays an important role in obesity.It is produced by fat cells. When working properly, it should tell your brain how high your fat stores are, resulting in reduced appetite which prevents an individual to overeat. However, its blood levels increase with higher fat mass, therefore leptin levels are especially high in people with obesity. This caused a reduced function of the hormone, called Leptin resistance, as it cannot cross the blood-brain barrier.
Sugar — When consumed in excess, sugar changes the hormones and biochemistry of your body which in turn contributes to weight gain. Added sugar is half glucose, half fructose. People get glucose from a variety of foods, including starches, but the majority of fructose comes from added sugar. Excess fructose intake may cause insulin resistance and elevated insulin levels. It also doesn't promote satiety in the same way glucose does.