INTRODUCTION:
Satiety centre is a group of cells in the Ventromedial Hypothalamus that when stimulated suppresses a desire for food. Satiety centre tells the organism when he/she has had enough to eat.[1] Removal of the satiety centre causes to eat continuously and he will grow far behind his normal weight.
Many of the stimuli that tell the hypothalamus that we are hungry originate in the organs of the body. If the nutrient level of the blood is too low, the hypothalamus is alerted and the feeding centre, initiates eating behaviour. External stimuli can also initiate eating behaviour. The sight, sound, and even the thought of food initiate impulses that eventually reach the feeding centre in the hypothalamus.[2]
The brain plays a crucial role in the decision to eat, integrating multiple hormonal and neural signals that convey information about the body's nutritional status [1]. Among the many factors that influence the decision to start or stop eating, such as social context, the amount of food left, and dietary restraint, the volume and energy content of the food consumed are most important. As more food is ingested, the feeling of fullness becomes stronger and the motivation to eat decreases[3,4]. However, when a certain food is eaten, its pleasantness and the motivation to eat more of it decrease gradually, even though the stomach is not yet full [2]. In this case, one is still motivated to consume other foods, particularly those with different sensory characteristics; ie, one is not satiated per se, but is satiated to the specific food that was consumed. This phenomenon has been termed selective satiety
This paper addresses the importance of satiation and satiety, both relate to the inhibition of eating. Satiation occurs at the time of eating and signals are induced by the ingestion of food substances as the meal progresses. Such signals have many origins: sensory, cognitive, digestive, and hormonal. Satiation signals bring eating to an end. After the end of an eating episode, a satiety begins and undergoes for some time before hunger returns. Satiation and satiety have to do with the inhibition of eating, they can potentially affect total intake and facilitate body weight control.
It is important to understand whether sweet-tasting foods and drinks exert a special influence on satiation and satiety. Their high tastiness could trigger overeating, at least in some individuals under certain circumstances.
Human desire for sweet taste spans all ages, races, and cultures. Human newborns exposed to different taste stimuli accept sweetness but reject bitter taste. Young children prefer those foods that are both familiar and sweet. Throughout evolution, sweetness has had a role in human nutrition, helping to orient feeding behaviour toward nourishing foods. Beginning with mother’s milk, liquids have been important sources of both energy and nutrients.[5]
Excessive consumption of sugar-sweetened beverages has been linked to rising rates of obesity in the United States and worldwide.[6]
Sugar-containing beverages that taste sweet include still and carbonated soft drinks, juice-based beverages, 100% juices, and flavoured milk. Beverages sweetened with high-fructose corn syrup (HFCS) rather than sucrose have come under particular scrutiny. The association between sweetened beverages and obesity rates rests largely on temporal trends and cross-sectional studies. [7]
However, although satiety and satiation are easy to define [1, 8], they are difficult to quantify [9]. As a result, the factors leading to satiety and satiation and, ultimately, to body weight control are a matter of considerable debate. Different outcomes can be achieved depending on the question posed, the study design, and the age and sex of the participants [10], so the evidence required to make claims on foods is not always clear[11].
The nerve impulses in the body travels in fractions of seconds but even the Satiety Centre becomes lazy as person starts his meal!
MATERIALS AND METHODS:
The study was done by giving out questionnaires online through the website www.surveyplanet.com to about 40 students, studying first year in Bachelor in Dental Sciences in Saveetha Dental College, Chennai, out of which only 39 of them responded.
The students were asked to answer a set of 10 questions. The first 4 questions were mainly to classify the gender and the food and beverages they have in their routine life. The next 5 was based mainly on the eating habits and control over the food. The last question was based to check the feedback from them if they will be cautious about their eating habits and control in the food intake if the investigator explained the reasons.
The questions included in the questionnaire are shown in figure 1and2
|
Gender о Male о Female
How many ml/l of soft drinks do you have per day о 1 lit о Zero о 500 ml о More than 1lit
On a scale of 1-10 how addicted are you to junk foods
о Value
Which type of food attracts and t empts you to have more and more о Junk food о Home food о Fast food о Chocolates and icecreams
Do you have control over your food о Yes о No |
Figure.1.
|
Do you still feel hungry after having a full meal Sometimes о No о Yes
Do you feel that you are over eating о No о Sometimes о Yes
If so, do you take control of your food in the next meal Sometimes о No о Yes
Are you aware of the fact that only after few minutes of the meal intake feel full о Yes о No
If the investigator explains the reason, are you ready to be cautious henceforth о Yes о No |
Figure 2
RESULTS :
Gender?
How many ml/lt. of soft drinks you have per day?
On a scale of 1-10 how addicted are you to junk foods?
1 4.62 10
Lowest Average Higest
Which Type of food tempts you to have more and more?
Do you have control over your food?
Do you still feel hungry after having a full meal?
Do you feel that you are over eating?
If so, do you do you take control of your food in the next meal?
Are you aware of the fact only after few minutes of the meal intake you feel full?
If the investigator explains the reason, are you ready to be cautious hence forth?
DISCUSSION:
The intake of beverages has changed dramatically over the past few decades, coinciding with an increased prevalence of obesity. Intakes of soft drinks, colas, other sweetened carbonated beverages, and fruit drinks with added sugar have increased dramatically, especially among youth, whereas the intake of milk has declined [12–14].
From the results we can observe that 50% of the participants do not consume soft drinks and 42% of them consume around 500ml of soft drinks per day and 5% consume more than 1lt per day and 3% consume 1lt per day. Also when they were asked on a scale of 1-10 how addicted they are to junk foods the highest was 10 and the least was 1 and the average was 4.62! Each one of us have different opinions and temptations on different types of food, so when they were asked which type of food tempts them to have more and more with the options like home food, junk food, fast food, chocolate and ice cream; 26% answered home food and 24% answered chocolate and ice cream and 26% answered fast food and 24% answered junk food. Most of us now a days do not have control over the food and which leads to many health problems, 18% of the people answered that they do not have control over their food and 82% of the people said that they do.
Most people say that if you are hungry, you should sit down and have a bite to eat. In some cases, however, you may be feeling hungry after eating and not know why. [15] It is even possible that you are hungrier after eating than before. This is actually more common than most people realise. It happens because hunger isn't controlled by only one part of the body; 46% of the participants answered that they sometimes feel hungry even after a meal and 33% of them answered they don't feel hungry!
More than a third of adults and 17% of children and teenagers in the United States are obese (Ogden et al., 2014).[16] Obesity is the second-leading cause of preventable death in the U.S. contributing to 300,000 deaths each year. The major cause of obesity is eating/consuming a lot of foods that are rich in cholesterol and calories. Intake of foods rich in fatty or cholesterol plays a very high role in increased prevalence of obesity.[17-21] 54% of the participants answered sometimes they do feel that they are over eating and 27% of them have answered they do not feel they are overeating. The former were asked if they will control it in their next meal, unusually 50% of them answered surely they would. 64% of the participants are aware of the fact that only after a few minutes of meal intake they would feel full. It feels good to see that 92% of the participants who attended the survey are ready to be cautious if we explain them about proper intake and when they will actually feel full and having a proper meal and not lead to over eating which will in turn lead to obesity. If we explain the same to the people out there we can actually control the population from being obese and prevent deaths caused due to obesity.
CONCLUSION:
The body is in a continual state of hunger, which is intermittently relieved by eating. This perpetual drive to eat is periodically suppressed by inhibitory impulses generated by such things as the presence of food in the gastrointestinal tract, the flow of nutrients into blood and other factors. After these "satiety factors" have dissipated, the desire to eat returns. [22]
Why is it important to understand the factors that control food intake? At least two major areas of import come to mind; Obesity is the most prevalent nutritional disease which is seen now a days in our society. Metabolic demands of people and animals increase with sickness or trauma, often in conjunction with anorexia. Sickness combined with anorexia leads to accelerated starvation.[23]
For many years, the hypothalamus was thought to be the key to control of food intake. This view derived from classic experiments in which food intake was studied in rats with lesions in various areas of the brain.[24] Such studies clearly identified two regions in the hypothalamus that dramatically influence feeding behavior; Lateral hypothalamus (hunger center) - animals with lesions in this area become anorectic and lose weight. Ventromedial hypothalamus (satiety center)-animals with lesions in this area overeat and become obese.
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