How do I find a particular food?
There are 2 ways to locate a food:
- Search for food by name: food name can be entered fully or partially and in any
order. For example, to locate orange juice, you can enter 'orang jui' or 'juice
orange', or any other variations in the edit control then hit the Return key.
- Browse a particular food group by selecting a group in the drop down listbox. Such
as selecting the Citrus Fruits, Juices category.
When multiple food items are listed, you can click on the column headers (Food Name,
Fiber, Sugars) to sort food by name or by nutrient content. Reverse the sort order
by clicking the same column header again.
What info does the Calorie Chart show?
The Calorie doughnut chart shows relative contributions to total calories
from carbohydrate, protein and fat (and alcohol, if exists).
If selected food item is very high (top 20%) in saturated fat, cholesterol, sugar,
fiber or protein, this info is shown when the mouse cursor hovers on this chart.
What is glucose?
Glucose, a monosaccharide (or simple sugar) also known as grape sugar or corn sugar,
is an important carbohydrate. The living cell uses it as a source of energy and
metabolic intermediate. Glucose is one of the main products of photosynthesis.
All major dietary carbohydrates contain glucose, either as their only building block,
as in starch and glycogen, or together with another monosaccharide, as in sucrose
and lactose. Some of the glucose goes directly toward fueling brain cells and erythrocytes,
while the rest makes its way to the liver and muscles, where it is stored as glycogen,
and to fat cells, where it can be used to power reactions which synthesize some
fats. Glycogen is the body’s auxiliary energy source, tapped and converted back
into glucose when there is need for energy.
What is galactose?
Galactose (also called brain sugar) is a type of sugar which is less sweet than
glucose. It is considered a nutritive sweetener because it has food energy. It is
found in dairy products, in sugar beets and other gums and mucilages. It is also
synthesized by the body.
What is fructose?
Fructose (also levulose or laevulose) is a simple reducing sugar (monosaccharide)
found in many foods and is one of the three important dietary monosaccharides along
with glucose and galactose. Honey, tree fruits, berries, melons, and some root vegetables,
such as beets, sweet potatoes, parsnips, and onions, contain fructose, usually in
combination with glucose in the form of sucrose. Fructose is also derived from the
digestion of granulated table sugar (sucrose), a disaccharide consisting of glucose
and fructose, and high-fructose corn syrup (HFCS).
Crystalline fructose and high-fructose corn syrup are often mistakenly confused
as the same product. The former is simply pure (100%) fructose. The latter is composed
of nearly equal amounts of fructose and glucose.
The primary food sources of fructose are fruits, vegetables, and honey. Fructose
exists in foods either as a free monosaccharide or bound to glucose as the disaccharide,
sucrose. Fructose, glucose, and sucrose can all be present in a food; however, different
foods will have varying levels of each of these three sugars.
In general, foods that contain free fructose have equal amount of free glucose.
Some fruits have larger proportions of fructose to glucose compared to others.
For example, apples and pears contain more than twice as much free fructose as glucose,
while apricots contain less than a half of fructose than glucose.
Apple and pear juices are of particular interest to pediatricians due to the juices’
high concentration of free fructose relative to glucose, which can cause diarrhea
in children. The cells of the small intestine, enterocytes, have lower affinity
for fructose absorption compared with that for glucose and sucrose. Unabsorbed fructose
creates higher osmolarity in the small intestine, which draws water into the gastrointestinal
tract, resulting in osmotic diarrhea.
What is lactose?
Lactose (also referred to as milk sugar) is a sugar that is found most notably in
milk. Lactose makes up around 2–8% of milk (by weight).
Infant mammals are fed on milk by their mothers, which is rich in the carbohydrate
lactose. To digest it, an enzyme called lactase (β-D-galactosidase) is secreted
by the intestinal villi. This enzyme cleaves the lactose molecule into its two subunits;
glucose and galactose for absorption.
Since lactose occurs mostly in milk, in most mammals the production of its digestive
enzyme, lactase, gradually decreases with maturity, due to lack of constant consumption.
Many people who live in Europe, the Middle East, India, and parts of East Africa,
maintain normal lactase production into adulthood. In many of these areas, milk
from mammals such as cattle, goats, and sheep is used as a large source of food.
Hence, it was in these regions that genes for lifelong lactase production first
evolved. The genes of lactose tolerance have evolved independently in various ethnic
groups.
What is sucrose?
Sucrose (common name: table sugar, also called saccharose) is a disaccharide of
glucose and fructose. It is best known for
its role in human nutrition and is formed by plants but not by other organisms such
as animals.
Sucrose is the most common food sweetener, although it has been replaced in American
industrial food production by other sweeteners such as fructose syrups or combinations
of functional ingredients and high intensity sweeteners. This is due to the subsidization
of corn in the United States, which has led to a vast surplus. Combined with sugar
tariffs, this has driven the price of corn syrup far below that of sugar.
Sucrose is the most important sugar in plants, and can be found in the phloem sap.
It is generally extracted from sugar cane or sugar beet and then purified and crystallized.
Other (minor) commercial sources are sweet sorghum and sugar maples.
Sucrose is ubiquitous in food preparations due to both its sweetness and its functional
properties; it is important to the structure of many foods including biscuits and
cookies, cakes and pies, candy canes, ice cream and sorbets, and also assists in
the preservation of foods. As such it is common in many processed and so-called
“junk foods.” Sucrose is an easily assimilated macronutrient that provides a quick
source of energy to the body, provoking a rapid rise in blood glucose upon ingestion.
Overconsumption of sucrose has been linked with some adverse health effects. The
most common is dental caries or tooth decay, in which oral bacteria convert sugars
(including sucrose) from food into acids that attack tooth enamel. Sucrose, as a
pure carbohydrate, has an energy content of 3.94 kilocalories per gram (or 17 kilojoules
per gram). When a large amount of foods that contain a high percentage of sucrose
is consumed, beneficial nutrients can be displaced from the diet, which can contribute
to an increased risk for chronic disease. It has been suggested that sucrose-containing
drinks may be linked to the development of obesity and insulin resistance. Although
most soft drinks in the USA are now made with high fructose corn syrup, not sucrose,
this makes little functional difference, since high fructose corn syrup contains
fructose and glucose in a similar ratio to that produced metabolically from sucrose.
The rapidity with which sucrose raises blood glucose can cause problems for people
suffering from defects in glucose metabolism, such as persons with hypoglycemia
or diabetes mellitus. Sucrose can contribute to development of the metabolic syndrome.
In an experiment with rats that were fed a diet one-third of which was sucrose,
the sucrose first elevated blood levels of triglycerides, which induced visceral
fat and ultimately resulted in insulin resistance. Another study found that rats
fed sucrose-rich diets developed high triglycerides, hyperglycemia, and insulin
resistance.
What is maltose?
Maltose, or malt sugar, is a disaccharide. Maltose can be broken down into two glucose
molecules by hydrolysis. In living organisms, the enzyme maltase can achieve this
very rapidly. In the laboratory, heating with a strong acid for several minutes
will produce the same result.
The production of maltose from germinating cereals, such as barley, is an important
part of the brewing process. When barley is malted, it is brought into a condition
in which the concentration of maltose-producing amylases has been maximized. Mashing
is the process by which these amylases convert the cereal’s starches into maltose.
Metabolism of maltose by yeast during fermentation then leads to the production
of ethanol and carbon dioxide.
Where to see Robert Lustig's Sugar: The Bitter Truth lecture?
Go to DietGrail.com Main Page