Lactose intolerance
Related Terms
Apovitellenins I, apovitellenins VI, dairy, diet, egg free diet, fruitarian, gastroenteritis, IBS, irritable bowel syndrome, lacto vegetarians, lactose, lactose intolerance, lysozyme, ovalbumin, ovomucoid, ovotransferrin, ovo vegetarian, phosvitin, vegan.
Background
A dairy free diet contains absolutely no dairy products; no milk, butter, cheese, cream or yogurt. People who follow a dairy free diet may include: lactose-intolerant individuals, individuals with irritable bowel syndrome (IBS), ovo vegetarians, fruitarians or vegans.
An egg free diet contains no eggs or foods made with any part of an egg. Many pastries, desserts and breads contain eggs and thus cannot be eaten with an egg free diet. People who follow an egg free diet may include: individuals with an allergy to eggs, fruitarians, lacto vegetarians and vegans.
Lactose intolerance is the inability to digest significant amounts of lactose, the major sugar found in milk. Lactose intolerance is caused by a shortage of the enzyme lactase, which is produced by the cells that line the small intestine. Lactase breaks down milk sugar into two simpler forms of sugar called glucose and galactose, which are then absorbed into the bloodstream. People may confuse lactose intolerance with cow's milk intolerance because the symptoms are often the same. However, lactose intolerance and cow's milk intolerance are not related. Being intolerant to cow's milk is an allergic reaction triggered by the immune system. Lactose intolerance is a problem caused by the digestive system.
Most people who are allergic to eggs are allergic to egg protein and may react to the proteins in the egg white. However, because it is impossible to completely avoid cross-contamination between yolks and white, people who are allergic to eggs need to avoid eggs completely. The most allergenic proteins in egg white are ovalbumin, ovomucoid, ovotransferrin and lysozyme. Lysozyme is an unlabeled additive used in cheese preparation. Egg yolk contains three proteins (apovitellenins I & VI and phosvitin) that are also allergenic.
Lacto vegetarians do not eat meat or eggs but do consume dairy products. Most vegetarians in India and those in the classical Mediterranean lands, such as Pythagoreans, are or were lacto vegetarian. Ovo vegetarians do not eat meat or dairy products but do eat eggs. Fruitarians eat a diet that consists of only raw fruit and seeds and other plant matter that can be gathered without harming the plant, and thus follow a dairy free diet. Vegans avoid eating or using any animal products, including eggs and dairy.
Many studies suggest that consuming dairy may have many health benefits including: providing calcium, protein, B vitamins, minerals, vitamin D, vitamin A and probiotics (beneficial bacteria). However, many studies also show possible negative effects of dairy including: arthritis pain, acne and increased risk for certain types of cancer. Additionally, conditions like autism, obesity and prostrate cancer have been linked to dairy consumption.
Egg free diets are often combined with a dairy free diet, particularly in the case of vegans or individuals allergic to both milk and eggs. Dairy free diets are becoming more popular with the increase in lactose-intolerance awareness, vegetarianism and new studies suggesting negative effects of dairy. Those following a dairy free diet are advised to make sure they get enough calcium, protein and vitamins from other food sources.
Theory / Evidence
Many people follow a dairy or egg free diet due to allergy or intolerance. For example, lactose intolerance, also called lactase deficiency, indicates an inability to fully digest milk sugar (lactose) in dairy products. The problem underlying lactose intolerance is a lack of lactase, an enzyme produced by the lining of the small intestine. Lactase breaks down lactose so that it can be absorbed into the bloodstream. A deficiency of lactase leads to problems in breaking down and absorbing milk sugar. The signs and symptoms of lactose intolerance usually begin 30 minutes to two hours after eating or drinking foods that contain lactose. Common signs and symptoms include: abdominal cramps, bloating, diarrhea, gas and nausea. Symptoms are usually mild but may sometimes be severe. The severity of symptoms does not correlate with the degree of lactose malabsorption. Instead, symptoms relate to a range of factors, including ethnicity, age and how fast a person digests food.
There are three types of lactose intolerance:
Primary lactose intolerance: Normally, the body produces large amounts of lactase at birth and in early childhood, when milk is the primary source of nutrition. Usually the lactase production decreases as the diet becomes more varied and less reliant on milk. This gradual decline may cause symptoms of lactose intolerance.
Secondary lactose intolerance: This form of lactose intolerance occurs when the small intestine decreases lactase production after an illness, surgery or injury to the small intestine. It can occur as a result of intestinal diseases such as celiac disease, gastroenteritis or an inflammatory bowel disease, especially Crohn's disease. This type of lactose intolerance may last only a few weeks and be completely reversible. However, if it is caused by a long-term illness, it may be permanent.
Congenital lactose intolerance: It is possible for babies to be born with lactose intolerance. This rare disorder is passed from generation to generation in a pattern of inheritance called autosomal recessive. This means that both the mother and the father must pass on the defective form of the gene for a child to be affected. An infant with congenital lactose intolerance is intolerant of the lactose in the mother's breast milk and has diarrhea from birth. These babies require lactose-free infant formulas.
A few risk factors can make a person or child more prone to lactose intolerance. They may include: age, ethnicity and premature birth. Lactose intolerance usually starts in adolescence and early adulthood; the condition is uncommon in babies and young children. A child with chronic diarrhea before age one usually has another underlying problem. Lactose intolerance is more common in certain ethnic and racial populations. Lactose intolerance is more common in African, African-American, Asian, Hispanic and Native American populations. Infants born prematurely (28 to 32 weeks of gestation) may have reduced levels of lactase, because this enzyme increases in the fetus late in the third trimester.
Egg allergy symptoms may include any of the common symptoms of food allergies, such as skin rashes or hives, gastrointestinal distress, or breathing problems. In severe cases, a life-threatening reaction called anaphylaxis may occur.
A study found that milk might not be an obesity fighter in children. The National Dairy Council's $200 million dollar, "3 A Day" campaign, claims that consuming three glasses of milk per day can help fight obesity. A study of more than 12,000 American children found that the more milk consumed, the more weight gained. Consuming more than three servings a day correlated to a 35% higher chance of becoming overweight. The Council based their claims on research that suggested elements in milk might cause the body to make less fat and speed its elimination. Such reports are not substantiated, and it is suggested that weight loss is only aided in adult systems when calories are cut as well. Weight gain in the studied children was attributed to the excess calories, estrone and whey protein in dairy products. The milk did prove successful in increasing energy levels.
The Dietary Guidelines for Americans (2005) recommends that Americans increase their intake of dairy products. However, some studies have reported that increasing dairy product intake is associated with an increased risk of prostate cancer. High intake of dairy products and calcium may be associated with an increased risk of prostate cancer, although the increase appears to be small.
Among the many reasons for following a dairy free diet is the notion that dairy foods may adversely affect the health of adults and children. In addition to the high content of cholesterol and saturated fat (excesses of which are the primary causes of atherosclerosis and heart disease), dairy products are a source of delayed food allergies with a variety of symptoms that may include: diarrhea, abdominal pain, eczema (skin rash), joint pain, gas, bloating, migraine headache, asthma, acne, fatigue, runny nose, diabetes and immune dysfunction. There is often a delay in the onset of these symptoms making them difficult to trace back to dairy. It is not until individuals entirely eliminate dairy products from their diet that they may experience relief and understand the connection between their consumption of milk products and these symptoms.
Researchers at the Harvard School of Public Health found an increased risk of ovarian cancer in those women who have a high intake of dairy products, particularly yogurt and cottage cheese. Galactose, the breakdown product of lactose, is believed to be the cause of the heightened risk.
Cow's milk may also be responsible for eliciting an autoimmune response that leads to diabetes mellitus in children. Studies of one of the proteins in cow's milk, bovine serum albumin (BSA), have indicated that BSA may instigate an autoimmune response that leads to the destruction of the beta cells of the pancreas.
Milk and other dairy products may contain hormones, pesticides, antibiotics and other chemicals.
Food allergy plays an important role in the pathogenesis of atopic dermatitis (red, itchy, dry skin). Exclusion of eggs and milk from the diet of children during the first few months of life has been proven to significantly reduce the severity of eczema in children aged between two and eight years. Clinical improvement was observed in 80% of cases after dietary exclusion. The younger children responded best, and the response to diet was not influenced by the severity of the eczema. No relation was observed between the family history of atopy and response to diet.
Overall, the evidence is mixed regarding the health benefits of a diet including or excluding eggs and dairy. However, in certain populations (i.e. those with allergies or intolerances), these diets are important lifestyle modifications.
Author information
This information has been edited and peer-reviewed by contributors to the Natural Standard Research Collaboration (www.naturalstandard.com).
Bibliography
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Businco L, Businco E, Cantani A, et al. Results of a milk and/or egg free diet in children with atopic dermatitis. Allergol Immunopathol (Madr). 1982 Jul-Aug;10(4):283-8.
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National Dairy Council. 19 June 2006.
NIH Lactose intolerance. National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). 19 June 2006.
Qin LQ, Xu JY, Wang PY, et al. Milk/dairy products consumption, galactose metabolism and ovarian cancer: meta-analysis of epidemiological studies. Eur J Cancer Prev. 2005 Feb;14(1):13-9.
United States Department of Health and Human Services (HHS). 19 June 2006.
Diet outline
Those who follow a dairy free diet consume absolutely no dairy products. Many substitute rice and soy products. People may or may not eat meat, fish, poultry, fruits and vegetables depending on their reasons for a dairy free diet.
Dairy substitutes may include: almond milk, apple, pear or prune puree, cheese alternatives (soy, rice), multi-grain milk, non-diary frozen desserts, oat milk, rice milk or soy milk. When baking, milk may be substituted, in equal amounts, with water or fruit juice.
Some hidden sources of milk may include: deli meat slicers that are frequently used for both meat and cheese products; some brands of canned tuna fish that may contain casein, a milk protein; many non-dairy products that contain casein (a milk derivative), listed on the ingredient labels; some meats that may contain casein as a binder; and many restaurants that may put butter on steaks after they have been grilled to add extra flavor.
Those following an egg free diet may avoid the following products because of their egg-containing potential: albumin, some baby foods, battered meat or fish, Bavarian creams, some beers, some breaded foods, some breads (particularly those with shine crusts, i.e. Portuguese sweet bread), cakes, some candy, some coffee, some cookies, consomm?s, creamed foods, creamed pies, cream puffs, croquettes, custards, doughnuts, egg beaters, egg noodles, egg rolls, egg whites, egg yolks, some egg substitutes, eggnog, fondue, French ice cream, fritters, frostings, hollandaise sauces, ice cream, marshmallows, mayonnaise, meringues, some muffins, pancakes, some pie fillings, powered or dry eggs, prepared meats, pretzels, puddings, root bears, some salad dressings, sausages, sherbets, some soups, souffl?s, tartar sauce, some wines and waffles. Other words that may indicate egg include: apovitellenins I & VI, globulin, livetin, lysozyme, ovalbumin, ovoglobulin egg albumin, ovomucin, ovomucoid, ovotransferrin and phosvitin. This list is not comprehensive and a qualified healthcare professional should be consulted for a complete list.
Some hidden sources of eggs many include: eggs used to create the foam or milk topping on specialty coffee drinks or used in some bar drinks; some commercial brands of egg substitutes contain egg whites; most commercially processed cooked pastas (including those used in prepared foods such as soup) that contain egg or are processed on equipment shared with egg-containing pastas; and fresh pasta.
When baking, eggs may be substituted for: 1 tsp baking powder, 1 tbsp liquid, 1 tbsp vinegar; 1 tsp yeast dissolved in 1/4 cup warm water; 1 1/2 tbsp water, 1 1/2 tbsp oil, 1 tsp baking powder; or 1 packet gelatin, 2 tbsp warm water.