When you hear the term "sugar" you likely think of the white crystals commonly known as table sugar. This type of sugar, called sucrose is just one type of sugar molecule. Two other common types include fructose found in fruit and lactose found in milk. The lactose sugar consists of two simple sugars — glucose and galactose — bound together to form a diasaccharide sugar. Lactose, which exists as different forms, including lactose monohydrate, triggers uncomfortable symptoms in those who suffer from lactose intolerance.
Types of Lactose
Scientists classify sugars as carbohydrates because they consist of carbon, hydrogen and oxygen molecules. Galactose and glucose each form a ring-shaped molecule bound together by an oxygen molecule to create lactose. The orientation of the carbon and hydrogen can change creating two types of lactose: alpha-lactose and beta-lactose. When transformed into the solid form, alpha-lactose crystallizes into lactose monohydrate. This name designation means that each lactose molecule is associated with one water molecule.
In nature, you find lactose in milk produced by mammals. All foods made from milk, including yogurt, cheese and ice cream also contain lactose. It serves as a good food source of energy and facilitates the absorption of calcium. Its ability to enhance flavor and color of foods, modify food texture and extend shelf-life also make it a desirable food additive. Food manufacturers make food-grade lactose monohydrate and add it to foods like baked goods, snack foods, frozen desserts, baby food, jams, sweeteners, meats, soups, sauces and a variety of other foods. For those who suffer from lactose intolerance, this makes eating a lactose-free diet more difficult.
Because lactose consists of two simple sugar molecules, it is too big for the intestines to absorb. Cells lining the small intestine produce and secrete an enzyme known as lactase that functions to break the bond between the glucose and galactose so your body can absorb the sugar and utilize the energy. As you age, your body slows its production of lactase, leading to a lactase deficiency. Without enough lactase you cannot digest lactose and it remains in the digestive tract. Once it enters the large intestine, the bacteria try to break down the sugar through a process of fermentation. This causes the symptoms of lactose intolerance, including excessive gas, abdominal pain, bloating, nausea and diarrhea.
Your doctor can diagnose lactose intolerance by performing a lactose tolerance test or a hydrogen breath test. Upon receiving your diagnosis, the best way to control your symptoms is to adopt a lactose-free diet. Although it may sound simple to remove milk and yogurt from your diet, so many foods contain lactose you must carefully read all ingredient labels to determine the lactose-free foods. Any ingredient that resembles milk, like milk solids, skim milk solids and milk powder contains lactose. Other ingredients derived from milk are not as easy to spot. Ingredients like whey protein, whey solids, sodium caseinate, artificial butter flavor, lactalbumin, rennet casein, lactoferrin and lactoglobulin also contain lactose. Consult your doctor or your dietitian for a complete list of ingredients that may contain lactose or lactose monohydrate.