Nowadays, the fashion trends and cosmetics industry promote fitness and “perfect” body types. Strict following of these “recommendations” may have harmful consequences. Social media do not help, promoting standards – to stay healthy and beautiful, measured in clothing sizes.
Usually, there is no room for being “just average”. A larger size means a larger problem. People that are obese are blamed for their weight. A few extra pounds won't hurt, but when you do too much. Good times came to the end. Have you ever wondered where the boundary between regular size, overweight, and obesity is? Or, what causes people to gain weight? Within this paper, we try to answer these questions.
Image credit: Pikrepo (free licence)
S like sweetness, and sugar
Humans require energy from carbohydrates (sugars) to stay healthy. Among many different sugars, the one most desired by our brains is glucose. It acts as fuel for our bodies. How? Once glucose is ingested, it enters the bloodstream, and its excess is stored as fat that stays in the body as the reserve of energy. Excess calories supplied to the body lead to an increase in body weight, resulting first in overweight, and later, in obesity. Insulin is crucial in the process of getting the glucose into the cells which need it – inadequate supply or action of this hormone leads to diabetes.
Sugars are divided into simple and complex ones. Glucose bases on just one molecule, while starch or xanthan gum are complex sugars that have many molecules inside. We can find simple sugars in natural food like fruit, vegetables, and milk. They give food a sweet taste. Complex sugars are contained in white bread, cakes, or pastries. Doctors recommend a dose fewer than 4 tablespoons of sugar a day, but let’s keep in mind that the term “sugar” means carbohydrates contained not only in sweets but also in starch-based products. Unfortunately, evolutionary we like the sweet taste and it is difficult to do not to eat it.
What about products that contain fat? We should not cut them off totally from our diet, because they are needed to absorb vitamins like A, D, E, K, and coenzyme Q-10. Moreover, dietary fats are essentials for cell growth. Without them, we would not produce certain hormones crucial to the adequate functioning of our bodies. We, therefore, require fat in our diet.
Two major types of fat exist, namely saturated and unsaturated fat. Saturated fats are less healthy, so should be avoided. In fact, an overdose of fats leads to their accumulation in the body as fatty tissue that is called adipose tissue, which is not easy to “burn” by exercises. An excess of fat in our diet, as well as an excess of sugars, leads to obesity.
O like overweight and obesity
Obesity is often defined as a condition wherein there is an excessive accumulation of fat in the body. This in itself may lead to serious health problems. In a nutshell, obesity is a complicated health condition. In recent years, obesity and diseases linked to it have become one of the major threats to human life.
Did you know that worldwide obesity has nearly tripled since 1975? In cases where weight reduction through proper diet and physical activity with the support of a specialist is not possible, the patient qualifies for weight-reduction (bariatric) surgery. People with severe obesity have an increased risk of death at a young age from cancer, heart disease, stroke, diabetes, and kidney disease or lungs.
Obesity affects the functioning of the whole body and can result in damage to or diseases of other organs, see Fig. 1. The effects of obesity are especially felt by the joints and bones. Too much weight contributes to their rapid degeneration. Obese people are thus predictably more susceptible to arthritis and pain caused by inflammation of joints and bones [1].
Figure 1. Schematic image of obesity and overweight effect on the body. Image credit: M. Osial
Unfortunately, fat also accumulates in the walls of blood vessels known as atherosclerotic plaques. They lead to difficulties in blood flow, raising the risk of cardiovascular diseases. As a consequence, the disorder of fluent blood flow causes insufficient oxygen supply also called tissue hypoxia. Why?
Blood transports oxygen to every single cell in our body. Reduced blood flow to cells causes reduced efficiency. Hypoxia occurs when oxygen levels are too low. There are also other health consequences of obesity like high blood pressure, high blood cholesterol, diabetes type 2, and sleep apnea, which leads to an increase in the risk of developing diseases such as stroke, several types of cancers, infertility, or even house gallbladder [2].
What is the cause of obesity?
Obesity can be genetic (some of us seem to have a “faster” metabolism than others), behavioral (lifestyle, excessive eating, physical inactivity), hormonal (level of enzymes in the body is disturbed) and metabolic (digestive system dysfunctions) influences on body weight, however, there may be other factors contributing to obesity like medical reasons (different diseases like Cushing syndrome and medicines like steroids) or psychological problems (lack of motivation, mental disorders).
What about ailments associated with obesity? Adult health problems are connected with breathing difficulties, unusual sweating, sleep disorders like snoring, skin problems, fatigue, inability to perform physical activities, joint pain, negative self-esteem, depression, shame, and even social isolation [3]. The problems that may appear during childhood include eating disorders, sleep disorders like sleep apnea, GI reflux, orthopedic problems, and breath shortness during physical activity.
From diagnosis to treatment
Body Mass Index (BMI) is an indicator that is a simple way to measure the proportions of your body: weight in kilograms divided by the square of the height in meters. The BMI in the range between 18.5 and 24.9 means that you are in a healthy weight range, while BMI 25-29.9 corresponds to overweight, and above 30 obese, respectively. Too low BMI is also not good, the BMI below 18.5 means being underweight which may also have a negative influence on health [4]. The spectrum of BMI and overweight/obesity status is shown in Figure 2.
Figure 2. BMI versus obesity and overweight. Image credit: M. Osial
There are multiple interventions that allow people to achieve proper weight ranging from lifestyle modification, through pharmacological therapy up to bariatric surgery. However, easier said than done. XXI century gives us a lot of food goods and we move less than in past. In general, weight reduction therapy is based on having a lower calorie diet (recently the keto diet is quite popular), and increasing physical activity [5].
Ultimately, if all else fails, people who have severe obesity can undergo bariatric surgery. These procedures typically modify the anatomy of the gastrointestinal system by forming a small pouch in the stomach and separating the rest of its volume allows the patient to consume only a small amount of food per session [6].
Summary
Obesity, considered a pandemic of the XXIst century, poses severe threats to human life. It can lead to cardiovascular disease, increasing the risk of myocardial infarction, hypertension, blood clots, and stroke. Obesity can also induce sleep apnea, inflammation, and subsequent degeneration of joints and bones (potentially leading to dislocation and fractures), type 2 diabetes, and blood lipid disorders and severely impair the quality of life of the patients. However, obesity is a disease that can, unlike many others, be prevented, treated, and cured. Only with adequate knowledge, assistance, and perseverance can it become a thing of the past.
This paper is a joint work of Agnieszka Pregowska (Institute of Fundamental Technology Research, Polish Academy of Sciences), Magdalena Warczak (Institute of Physical Chemistry, Polish Academy of Sciences), Karol Masztalerz (the University of Manchester, Faculty of Science and Engineering), and Magdalena Osial (Faculty of Chemistry, University of Warsaw) as a part of the Science Embassy project. Images Credit: M. Osial
References
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