WHY ADDED SUGAR IS UNHEALTHY
Dietary sugar from plants is mainly Sucrose, a di-saccharide of Glucose and Fructose molecules in a 1:1 combination.
Fructose is the sweetest of all the naturally occurring carbohydrates; it is responsible for the sweet taste of fruits and honey.
Table sugar is the Sucrose prepared from Sugar Cane and Sugar Beets. After ingestion, Sucrose is broken down by the intestinal Enzyme Sucrase, into equal portions of Glucose and Fructose, which are then absorbed into the general circulation.
In addition to Sucrose, the other major source of Fructose is High Fructose Corn Syrup (HFCS), which was introduced in the early 1970s as an additional sweetener
HIGH FRUCTOSE CORN SYRUP (HFCS)
HFCS is a major ingredient in Soft drinks, Pastries, Desserts, and various Processed foods
Corn starch consists of 100% polymer of Glucose molecules.
Corn starch becomes a syrup when the starch is broken down into individual glucose molecules.
Manufacturers then add enzymes to the corn syrup to convert some of the Glucose to Fructose.
Fructose is much sweeter than Glucose.
HFCS consists of Fructose and Glucose mixed in a variety of concentrations.
HFCS 55 has 55% Fructose in it. HFCS 42 denotes 42% Fructose; the rest is glucose and water.
NATURAL SUGARS AND ARTIFICIAL SWEETNERS
Sucrose from plants are not readily absorbed into the circulation, once ingested.
Digestive enzymes are required to breakdown plant Sucrose to release the Fructose and Glucose.
Plant sucrose is also rich in Fibers and Vitamins including Vitamin C, (which helps the kidneys to remove Uric Acid from the body).
So, ingesting Sucrose from plants sources is practically safe and healthy.
On the other hand, Table Sugars and the HFCS are already processed and requires no digestive enzymes to release the Glucose and Fructose into the circulation.
The Human body is not capable of controlling and regulating the metabolism of Fructose. Any fructose ingested into the body undergoes an unregulated metabolic pathway.
It is the Table Sugars, and the HFCS that escape digestion, metabolic regulations that cause Health Problems.
HIGH FRUCTOSE CONSUMPTION AND ELEVATION OF SERUM URIC ACID LEVELS.
In the cells, the energy for metabolic activities is stored in the form of a chemical compound, Adenosine-Tri-Phosphate (ATP).
Adenosine in ATP is formed from Adenine, a Purine chemical compound that together with Guanine, form the building blocks for DNA, RNA
During the initial step of fructose metabolism, ATP donates a phosphate-group to Fructose to form Fructose-1-Phosphate (F-1-P).
F-1-P is the form of fructose that the body uses for metabolic activities.
After donating a Phosphate-group to Fructose, the remnant of the ATP (mainly AMP) is further broken down by cellular enzymes to generate the insoluble product known as Uric Acid.
Uric acid represents the final product of purine metabolism. This is because Humans do not have the enzyme Uricase that degrades Uric Acid to a soluble product, Allantoin.
The Kidneys eliminate about 200mg of Uric Acid per day (coffee consumption, and Vitamin C aids the kidneys to eliminate more of the Uric Acid), the Intestines about 100 mg/day.
Fructose appears to be the only Carbohydrate that when consumed generates Uric Acid.
In the cells, the conversion of Fructose to Fructose-1-phosphate requires energy expenditure from ATP.
The higher the ingested amount of fructose, the greater the requirement for ATPs.
Regular high fructose consumption is associated with high serum levels of uric acid, and the explanations that,
High fructose consumption leads to ATP depletion (the ATP is used to generate F-1-P).
ATP depletion forces the body to generate more Adenine (to be used in the production of ATP).
The more of Adenine generated the greater they are degraded into Uric Acid.
Persistent elevation of serum levels of uric acid can lead to Gout, and have also, been associated with several medical conditions, including
. Metabolic Syndrome
. Abnormal lipids
. Cardiovascular diseases
. Kidney diseases.
WHY IS NATURAL SUCROSE BETTER?
A recent study from Brazil showed that natural fruit juice consumption did not cause an elevation of serum uric acid levels in men.
Fruits and fruit juices are considered a source of fructose, fiber, and antioxidants, such as carotenoids and vitamin C, the latter of which has a uricosuric effect.
Although some studies have found an association between fruit juice and high uric acid levels, there was no greater chance of developing hyperuricemia with the increased intake of fruit juice in the present study.
The availability of vitamin C and fiber in fruit juice seem to compensate for the deleterious effects of fructose.
Sugar-Sweetened Soft Drinks and Fructose Consumption Are Associated with Hyperuricemia: Cross-Sectional Analysis from the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil)
HIGH FRUCTOSE CONSUMPTION AND METABOLIC SYNDROME.
High fructose consumption induces insulin resistance and other manifestations of metabolic syndrome in a series of animal models. These effects are not seen in animals fed either glucose or starch
Metabolic syndrome is the name for a group of risk factors that raises one's risk for heart disease and other health problems, such as Diabetes and Stroke.
The 5 risk factors include:
. Excess Body Fat around the Waist
. A high level of serum Triglycerides
. A low level of Good HDL-Cholesterol
. An elevated systemic Blood Pressure
. An elevated Fasting Plasma Glucose
Simple Sugars are added to drinks and beverages as sweeteners.
Table Sugar (Sucrose) a disaccharide of Glucose and Fructose in a 1:1 ratio,
and High Fructose Corn Syrup are the two popular sweeteners.
In the liver, Fructose is used to generate more:
The greater the consumption of Fructose (from drinks and foods), the higher the levels of serum Triglycerides.
Excess amount of Triglyceride in the body, is stored as White fat, in the liver and other places.
High level of triglycerides leads to the generation of the Bad Cholesterols (VLDL-Cholesterol, and LDL-Cholesterol).
The more of Fructose one consumes, the higher the level of fat storage in the liver, fat cells and blood vessels.
Too much Fat in the body leads to Obesity.
High levels of Triglycerides and Fructose makes the liver cells store more Fat rather than burn it.
So, in effect, high fructose consumption equates to adding more fat to the diet.
URIC ACID AND SYSTEMIC BLOOD PRESSURE.
Uric acid may raise systemic blood pressure in several ways.
. Uric acid is pro-inflammatory. The levels of systemic inflammation markers such as C-reactive protein (CRP), tumor necrosis factor or chemokine are elevated in hyperuricemia.
. Uric acid activates the renin-angiotensin system, and further contributes to vascular smooth cell growth, and arterial function impairment and stiffening.
. Uric acid decreases nitric oxide production. Nitric oxide keeps the smaller blood vessels patent. A decrease in nitric oxide production contributes to renal vasoconstriction and therefore, Hypertension.
It has also been observed that Persistent vasoconstriction may contribute to arteriosclerosis and the subsequent development of salt sensitive hypertension, even when the hyperuricemia has been corrected.
Artificial sweeteners including Table Sugar and HFCS dump excess amount of Fructose and Glucose on the body.
The body has a way of regulating the Glucose uptake and metabolism through hormones like Insulin, and other chemical compounds.
Unlike Glucose, the body has no means of regulating Fructose uptake and metabolism. Unregulated metabolism of Fructose leads to
. intracellular ATP depletion
. Production of Uric Acids that in excess amount, is harmful to the body
. White Fat storage in the Liver, Fat tissues and blood vessels leading to weight problems, Obesity and Atherosclerosis.
To live healthier, and longer lives, most people need to move more and eat better including getting fewer calories from added sugars. Avoiding added sugar is ideal. For those who love added sugar, the A.H.A has a suggestion for them.
The American Heart Association suggests that men consume no more than 150 calories (about 9 teaspoons or 36 grams) of added sugar per day. That is close to the amount of sugar in a 12-ounce can of soda. For women it is no more than 100 calories per day (25 grams or 6 teaspoons per day).
Alex Sarkodie, MB. ChB.