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?

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