Studies have shown that diet plays a vital role in maintaining a healthy body weight and also to prevent obesity. The composition of diet is with macro and micronutrients. The macronutrients are carbohydrates or sugars and complex sugars, proteins and fats.
Image Credit: Marcos Mesa Sam Wordley
In a new study, researchers from the USDA-Agricultural Research Service Grand Forks Human Nutrition Center decided to study the effects of adding a small serving of a sugar-sweetened beverage to meals. They then analysed the effects this had on appetite, emerge metabolism and utilization and also oxidation of substrate (break down of the carbohydrates into smaller glucose particles for usage of the body for energy).
For the study the researchers recruited 27 adults who had an average age of 25 years and a Body mass index of 23 kg/m2.
The participants were offered either a sugar sweetened beverage or a non-nutritive-sweetened beverage along with a standard (15%E) or high- (30%E) protein meal. For both the groups meal carbohydrate contents were adjusted so that the participants received equivalent calories.
Same foods were used for all meals. So a total of 17g of fat and 500 calories that did not come from the beverages. Special room calorimeters were used for measurements.
The study visits were separated by at least 1 week. Menstruating women in the study were studied during the luteal phase (Days 15–20 of the monthly cycle).
Thus to simplify, the participants were studied for two 24 hour periods one week apart. They were given protein based meals with sugared drinks in the first experiment. They were given protein based meals along with non-sugary drinks.
Statistical analysis of the other factors sex, level of protein intake, type of beverage offered and its effects on appetite, satiety, taste profiles etc. were made. In addition diet-induced thermogenesis (DIT) and rates of substrate oxidation was also seen. DIT refers to production of body heat after a meal that can be measured using specific instruments.
Results of the study showed that the participants who had high dietary protein had lower hunger and improved satiety or sense of fullness after a meal. Looking at gender differences it was seen that men were hungrier and less satisfied after the meals than women participants. Increasing the protein in diet also reduced the desire to snack on something fatty, or salty or tastier. Men with these taste profiles had a bigger appetite. Desire to snack on something sweet was not influenced by gender of the participant or amount of dietary protein and type of beverage offered. When given a sweet beverage the participants showed a supressed DIT and also reduced oxidation of fat or breakdown of dietary fats.
Researchers could conclude from the study that appetite, sensations or desires for snacks and tasty foods as well as energy breakdown and oxidation of the substrate is significantly changed in response to the changes in the composition of the diet. Sweet beverage addition for example notably reduces the energy efficiency from foods and oxidation of fats irrespective of other components of the solid diet.
This means that addition of sugars to diet can reduce the breakdown of fats that can get deposited in the body. When taken with high proteins this can be worse.
Dr. Shanon Casperson, the lead author explained that one third of the calories that came from the sugared drinks were not used as energy and the fats got stowed away. Further less energy was used to metabolize or utilize the energy that came from meals.
Researchers also said that this study was in health weight participants and obese individuals’ body may react in different ways. However, Casperson says that that it is detrimental and the insight this study provides into how detrimental it is.
Sugar and Obesity
Sugar-sweetened beverages (SSBs) or sugary drinks are the major contributors to added sugars in the diets of most Americans. This leads to weight gain, obesity, type 2 diabetes, kidney disease, eye problems, non-alcoholic liver disease, heart disease, tooth decay, arthritis etc. Reducing these in diet can contribute to a balanced diet and eventually a healthy weight. Sugar-sweetened beverages are drinks that have corn sweetener, corn syrup, brown sugar, honey, lactose, malt syrup, maltose, sugar, sucrose, molasses, glucose, dextrose or fructose.
Sodas, fruit beverages, sports drinks, sweetened waters, sugared coffee and tea etc. are common examples.
According to the World Health Organization (WHO) in 2005 approximately 1.6 billion adults over the age 15+ were overweight, at least 400 million adults were obese and at least 20 million children under the age of 5 years were overweight.
The numbers have swollen to vast proportions over the past decade. Overweight and obesity are defined by the WHO as abnormal or excessive fat accumulation that presents a risk to an individuals’ health.
Overweight and obesity are major risk factors for a number of chronic diseases. A crude population measure of obesity is the body mass index (BMI) which is a simple index of weight-for-height that is commonly used in classifying overweight and obesity in adult populations and individuals - a person's weight in kilograms is divided by the square of the height in meters (kg/m2).
The WHO defines an adult who has a BMI between 25 and 29.9 as overweight - an adult who has a BMI of 30 or higher is considered obese - a BMI below 18.5 is considered underweight, and between 18.5 to 24.9 a healthy weight.