Obesity and overweight
One of the most common problems associated with the current lifestyle is overweight. The obesity or excess weight is one of the major risk factors in the development of many chronic diseases including respiratory and cardiac diseases, diabetes mellitus or non-insulin diabetes type 2, hypertension, some cancers, and premature death. New scientific studies and data from life insurance companies have shown that health risks of excess body fat may be associated with small increases in weight and not just a pronounced obesity.
The obesity and overweight are serious problems that pose an increased economic burden on national resources. Fortunately, this evil can be prevented to a large extent when introducing appropriate changes in lifestyle.
What is obesity and excess weight?
The obesity is simply defined as an abnormal state of health or excessive fat accumulation in fatty tissue (adipose tissue) from the body, it can be a serious health hazard. The underlying cause is a positive energy balance, which results in weight gain, i.e. when the calories consumed exceed the calories spent.
To help everyone easily determine what their weight is, simply the relationship between weight and height is measured, which is called Body Mass Index (BMI). BMI is a useful tool that is commonly used by physicians and other health professionals to determine the prevalence of weight below normal, overweight and obesity in adults. It is obtained by dividing weight in kilograms by a person between the square of height in meters (kg/m2). For example, an adult who weighs 70 kg and whose height is 1.75 m will have a BMI of 22.9 kg/m2.
It is considered that there are overweight and obesity when the BMI is above 25 and respectively 30. Normally, it is considered that BMI is a 'healthy' when it is between 18.5 and 25, which is "at risk" when it is 25-29, and "high risk" when it is above 30 [1].
Body Mass Index
- <18.5 weight below normal
- 18.5 – 25 Healthy Weight
- 25-30 Overweight
- > Obesity 30
But BMI does not give us information on the total amount of fat, or the way that fat is distributed in our body, which is important because excess abdominal fat can have negative health consequences.
One way to determine the distribution of fat is to measure the perimeter of the waist [2]. The perimeter of the waist has nothing to do with weight, and is a simple and practical method of identifying why people are overweight and therefore at increased risk of obesity-related diseases. If the perimeter of the waist is greater than 94-102 cm for men and 80-88 cm in women, there is an excess of abdominal fat that can pose an increased risk of health problems, including if your BMI is normal [3,4].
As measuring waist perimeter, these people are divided into two categories: Those with android distribution of fat (commonly known an "apple"), meaning that most of their body fat is intraabdominal and it accumulates in the stomach and chest, and is at increased risk of developing obesity-related diseases. And people with a ginoide distribution of fat (commonly known as a "pear"), meaning that most of the body fat is accumulated in the hips, thighs and buttocks, there may mechanical problems (joints, inner thighs), in extreme cases. Normally, the fat distribution in obese men is in the form of "apple" and women as a "pear" [5].
The dynamics of energy balance: the key
Fundamental principle of energy balance is:
Changes in energy reserves (fat) = energy intake (calories) – energy expenditure
There are several factors that influence the overweight and obesity , including genetic predisposition, environmental and behavioral factors, aging, and pregnancy [6]. What is clear is that obesity is not always the result of an abuse of the consumption of palatable food, or lack of physical activity. The biological factors can also influence too: hormones, genetics, stress, drugs and aging.
Dietary factors and frequency of physical exercise have a major influence on the equation of energy balance, but also consider factors that are more easily modifiable. In fact, the most closely associated with the increased prevalence of obesity in the whole world is high fat diets [7] and excessive energy [8, 9] and sedentary [10 , 11]. Conversely, losing weight when energy intake is less than energy expenditure over a long period of time. Generally, to lose weight steadily, dietitians recommend a diet low in calories combined with increased physical activity [12]. To learn more about physical activity or healthy eating.
Wonderful or miraculous diets should be avoided as dramatically limit the intake of calories or the variety of foods that can be consumed as they usually involve a lack of important nutrients, and / or difficult to maintain for long periods. Also, not having correct eating habits can become what's known as yo-yo diet (fat and slim down sharply as a result of dieting and then eating in excess). These yo-yo diets can be dangerous in the long term to the physical and mental health. We should not set goals too optimistic to make a diet as a loss of 10% over the initial weight and bring us significant benefits [13].
What are the trends with regard to obesity and excess weight?
Now seems that there is evidence to suggest that there is prevalence of overweight and obesity in the world, it is growing dramatically in the world, and that the problem is increasing both in children and adults.
The most comprehensive data on the prevalence of obesity in the world are those of the MONICA Project: Monitoring trends and determinants in cardiovascular disease ( Monitoring of Trends and Determinants in Cardiovascular Diseases study ) [14]. Together with information obtained in national surveys, the data indicate that the prevalence of obesity in most European countries has grown at around 10-40% in the last 10 years, between 10-20% in men and 10-25% in women [15]. The most alarming increase has been observed in Britain, where talking to adults, almost two thirds of men and half of women suffer from overweight or obesity [16].
Between 1995 and 2002, obesity among boys in England almost doubled since it went from 2.9 to 5.7% of the population, and among girls increased from 4.9 to 7.8%. One in five boys and one in four girls are overweight or obese. Among men of 16 to 24 years, obesity increased from 5.7 to 9.3% and among women the same age increased from 7.7 to 11.6% [17]. The International Obesity Task Force includes the most significant data.
What are the consequences of obesity and overweight for health?
The implications of obesity and overweight can have on are many and varied consequences, from a higher risk of premature death, a number of debilitating illnesses and psychological, which are not fatal but can have a negative effect on quality of life [18].
The main health problems associated with obesity and excess weight are:
- Type 2 diabetes
- Cardiovascular Diseases and Hypertension
- Respiratory diseases (sleep apnea syndrome)
- Some types of cancer
- Osteoarthritis
- Worsening of Psychological problems in the perception of quality of life
Degree of risk depends, among other things, the relative amount of excess weight, the location of body fat, how much has been gained during the adult age and the amount of physical activity. Most of these problems can be improved by thinning a bit (between 10 and 15%), especially if the person also increases physical activity.
Type 2 Diabetes
One from these serious diseases is type 2 diabetes (which usually develops in adulthood and is associated with overweight) or non-insulin diabetes mellitus, which is more linked to obesity and overweight. In fact the risk of developing type 2 diabetes increases with a BMI that is well below the threshold of obesity (BMI 30). The likelihood that obese women develop type 2 diabetes is 12 times higher than in women with a healthy weight. The risk of this type of diabetes increases as the BMI is higher, especially in people with a family history of diabetes, and decrease if you lose weight [19].
Cardiovascular disease and hypertension
Cardiovascular diseases include heart disease, stroke and peripheral vascular disease. These diseases are responsible for a large proportion of deaths (one in three) in men and women in industrialized countries and its incidence is also increasing in developing countries.
The obesity predisposes individuals to several cardiovascular risk factors, including hypertension and high blood cholesterol levels. In women, obesity is the most important variable in heart disease, after age and blood pressure [20]. The risk of suffering a heart attack is about three times higher in an obese woman in a thin woman of the same age.
Obese people are more likely to have high levels of blood triglycerides (blood fats) and LDL cholesterol with low density lipoprotein ("bad cholesterol") and low HDL cholesterol levels with high-density lipoprotein (“cholesterol good"). This is a characteristic metabolic profile in obese people with high accumulation of abdominal fat ( "apple") and is usually associated with an increased risk of coronary heart disease. Usually, if you lose weight, levels of blood lipids (fats) are better. If you lose 10 kg, you can produce a 15% decrease in LDL cholesterol levels and an increase of 8% in HDL cholesterol [21].
The relationship between hypertension (high blood pressure) and obesity is well documented and it is estimated that the proportion of hypertension attributable to obesity is 30-65% in Western populations. In fact, blood pressure increased when the BMI increases, for every 10 kg of weight gain, blood pressure goes up 2-3mm Hg. Conversely, if weight loss reduces blood pressure, and typically, for every 1% reduction in weight, blood pressure decreases 1-2mm Hg.
The prevalence of hypertension in overweight adults is three times higher than in adults overweight, and risk of hypertension in people with excess weight between 20-44 years is almost 6 times higher than in adults with normal weight.
Cancer
Although the relationship between obesity and cancer is not well defined, several studies have found that being overweight is associated with the incidence of certain cancers, notably cancers of gastrointestinal origin and hormonal. It has been observed that obese women have a higher risk breast cancer, endometrial, ovarian and cervical, and there is evidence that in men there is a higher risk of prostate cancer and rectal cancer. The clearest association is between colon cancer and obesity, which triples the risk in women as in men.
Osteoarthritis
Degenerative diseases of joints, the knee are normal complications associated with obesity and overweight [22]. It is thought that the mechanical damage of the joints is due to excess weight they have to endure. It is also more common in obese people back pain, which may be a major cause of absenteeism in obese people.
Psychological aspects
Obesity is considered a scourge in many European countries, and is perceived as a non-desirable physical appearance and a sign of the defects of character that is supposed to indicate. Even obese children from six years receive insults of other children as "lazy, dirty, stupid, ugly, liars and cheats" [23].
Obese people have to face discrimination. According to studies conducted in the United Kingdom and United States, young women with excess weight gain far less than healthy women, or other non-overweight women with chronic health problems [24].
Also more common for obese people to eat compulsively, and who have a long history of eating disorders that are characterized by binge and changes in weight [25].
What is the economic cost of overweight and obesity?
International studies on the economic costs of obesity have been shown to represent between 2% and 7% of total healthcare costs, although these percentages depend on the method of analysis used. In France, for example, the direct cost of obesity-related diseases (including staff costs for health care, hospital care, medical services and drugs for diseases with a proven relationship with obesity) amounted to 2% of total expenditures health [26]. In the Netherlands, the proportion of total medical costs attributable to obesity and excess weight is approximately 3-4% [27].
In England, the annual cost of obesity and its treatment to the National Health Service (NHS) approximately £ 500 million, and estimates its impact on the economy is 2.000 million pounds to year. The human cost of obesity is estimated 18 million days lost per year and 30,000 deaths per year, which will result in 40,000 lost years of working life and life expectancy decline in nine years [28] .
What is the collective responsibility of promoting healthy lifestyles?
We need the active participation of many groups, including governments, health professionals, the food industry, media and consumers to encourage consumption of healthy diets and increased physical activity, contributing to control overweight and obesity. This shared responsibility is to help promote healthy diets that are low in fat and high in complex carbohydrates and also contain large amounts of fresh fruits and vegetables.
It is a clear we need to put more emphasis on the benefits of physical activity, especially if one takes into account the growing urbanization and an aging population and increase in time spent on sedentary activities.
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