Factors that influence body mass

There are several factors that affect body mass. The factors were grouped into two categories, namely internal and external factors. Internal factors include heredity factors such as genes, thermal regulation, and metabolism. External factors include physical activity and food intake.
Internal factors

Internal factors responsible for body mass is a factor that can not be consciously controlled by the people who go on a diet.
Genetic factors
INSIG2

Research conducted by Boston University Medical School found that a gene called INSIG2 responsible for obesity. INSIG2 gene responsible for menginhibisi synthesis of fatty acids and cholesterol. Some of the protein product of the INSIG2 gene variant had a lower inhibitory power so that people with this gene variant will tend to accumulate more fat in their bodies. Approximately one in ten people (10%) suspected of carrying the gene variant.
FTO

Other genes responsible for obesity gene FTO is. FTO is the name of a gene located on human chromosome 16. Based on the results of research the people who had certain variants of FTO and has a homozygous variant allele pairs in its genome (16.4% of study subjects) had a weight of 3 kg heavier than ordinary people and have a risk of obesity , 5 times larger than the usual .
Thermal regulation

Man is essentially a warm-blooded creatures that spend energy to maintain body temperature. In addition to the energy needed to maintain body temperature (average of 37 ° C), an amount of energy is also required to maintain the activity of vital organs like the heart and lungs. The necessary energy is derived from the food consumed by someone.

Generally, in a state of sleep, humans need the power of 1 Watt for every kg of body weight (men with a body weighing 65 kg would consume about 65 watts, or roughly equivalent to the power needed to turn the two light bulbs). With body weight 65 kg, then the energy consumption required by that person every day is about 5,500 kilojoules or 1,400 kilocalories (kcal). The energy required for mere humans to live (in a state of rest), without doing any activity was called the Basal Metabolic Rate (metabolite Basic Rate / BMR).

Thermal regulatory mechanisms of each person is different and the energy consumption that determines how much nutrients to be burned by the body to produce energy. Thus, the higher the BMR one, the higher the energy consumption and the person requires more food to maintain body activity. Differences in gender, race, height, and also affect the BMR. Psychological conditions and air temperature also affected.

Because the total calorie needs for each individual is different and depends on gender, age, and even ethnicity. Nutritionists generally use the Harris Benedict Formula to produce a more accurate estimate of the value of a person's BMR. Instead of counting his own, when there are many internet sites that have provided a simple program to calculate the example program named BMR BMR Calculator.
Metabolism

Metabolism, in brief, is the treatment process (formation and decomposition) substances needed by the body to perform its functions. Lipid metabolism is one factor in the diet. A person can increase fat burning by increasing muscle mass in the body. As muscle mass increases, the metabolism of food will increase. This process will increase the value of BMR and caloric needs.
External factors

Based on research conducted on the population of the United States, there are 60.5% of the population aged adults have the condition of excess body weight (data of 2005) . Based on these data, some experts believe that the eating habits of life and hold a more dominant factor in influencing a person's weight when dibandngkan internal factors. Two external factors are the dominant physical activity and nutrition. A person can easily lose weight without the need to consume fat-burning drugs and the like by increasing the activity and reduce food intake into the body.
Physical activity

To perform physical activity, people need some energy. If the energy supplied by food is not enough, then the energy gained from the breakdown of fats in the body. The following are examples of physical activity along with the calories burned per hour (in kcal / h) which required any such activity