February 2020 Issue
Spotlight on Lactose-Free Dairy
By Mindy Hermann, MBA, RDN
Today’s Dietitian
Vol. 22, No. 2, P. 30
New products and technologies enable consumers to enjoy dairy and get the nutrients they need.
Exciting new product innovations in the lactose-free dairy category continue to draw consumers who would otherwise bypass the aisle.
The marketplace for lactose-free products had been relatively limited and stable in the years after the increased availability of lactase enzymes. Options generally featured lactose-free milk and ice cream, along with lactase products for consumers to use with conventional dairy products.
But with the increasing popularity of plant-based and naturally lactose-free alternatives to milk and yogurt, the dairy industry has sharpened its focus on eliminating lactose from more of its products. The recent expansion beyond milk and into yogurt, kefir, cottage cheese, and other dairy products—previously avoided by those who can’t handle lactose—enables people who are lactose intolerant to benefit from the variety and nutrient package dairy delivers. Equally exciting are new technologies to reduce lactose while often enhancing nutritional attributes of dairy products.
Overview of Lactose Intolerance
Lactose intolerance is defined as an inability to digest lactose, the primary carbohydrate in dairy milk. The enzyme lactase, required for lactose digestion, is produced by the villi in the small intestine. Lactase breaks down lactose from beverages and foods into two simple sugars, galactose and glucose. These sugars then are absorbed through the intestinal wall and into the bloodstream.
Lactose intolerance can result from a primary lack of adequate lactase production, the most common cause and often occurring with age, or a secondary inadequacy resulting from inflammatory bowel disease, celiac disease, malnutrition, or other conditions that damage the surface of the small intestine and/or cause atrophy of intestinal villi. People with lactose intolerance can develop symptoms of abdominal pain, bloating, gas, nausea, and/or diarrhea shortly after consuming lactose or up to several hours later. This occurs due to a combination of gut bacteria converting lactose into simple sugars in the large intestine—lactose acting as a prebiotic—and the increased presence of fluid in the large intestine to dilute the undigested lactose and resultant simple sugars.
Lactase production in the intestine typically is strong in infancy and begins to decline in early childhood, although some infants have a defect in the LCT gene that prevents them from tolerating nonbreastmilk sources of lactose. (Breastmilk contains both lactose and the enzyme lactase.) A majority of adults around the world are lactose intolerant.
Across the spectrum of lactose intolerance are people who can’t digest even small amounts and people who can handle a modest dose, according to Kate Scarlata, RDN, LDN, a Massachusetts-based digestive health expert and coauthor of The Low-FODMAP Diet Step by Step. “Monash University in Melbourne, Australia, sets a threshold of 0.5 g of lactose per eating occasion for people who cannot tolerate lactose, but I’ve observed that many of my clients can handle up to 6 g of lactose, the amount in half a cup of fluid milk, per sitting.”
Body size and genetic differences also influence degree and symptoms of intolerance.1 People with a larger body mass and those from dairy-consuming cultures tend to be able to handle larger amounts of lactose at a time. Globally, about two-thirds of adults lose some or all of their ability to tolerate lactose after infancy because of decreased expression of the LCT gene and the regulatory MCM6 gene over time. Lactose intolerance is most common among populations of indigenous North American, East Asian, West African, Arab, Jewish, Greek, and Italian descent, and least prevalent in populations from Northern Europe and other regions whose diet regularly includes unfermented dairy products.2 People who are intolerant of lactose are more likely to develop symptoms after consuming conventional fluid milk, yogurt, sour cream, and dairy desserts, as well as whey protein, and least likely to react to hard cheese and other dairy products containing only small amounts of lactose.
Lactose on Labels
Lactose content is represented by the amount of carbohydrate and total sugars on the Nutrition Facts panel of an unsweetened or dairy product or one sweetened with nonnutritive sweeteners. In milk and dairy products that don’t contain sugar or other nutritive sweeteners, the amount of total sugars listed on the label represents lactose content. For example, one cup of plain fluid milk contains 12 g carbohydrate, all from lactose; a lactose-free milk produced traditionally by adding lactase contains the same amount of total sugars as in the milk before treatment with lactase. The now lactose-free milk will taste sweeter than nontreated milk because the lactose has been converted to the simple sugars glucose and galactose. Lactose-free milk doesn’t contain added sugars; any added sugars listed on the Nutrition Facts panel can be attributed to nutritive sweeteners such as cane sugar, honey, and others.
Government guidance for a lactose-free claim on fluid milk doesn’t exist in the United States. Globally, lactose-free products generally reduce lactose down to 0.5% or 0.1%, although some countries require a reduction down to <0.01%.3
Lactose-Free Fluid Milks
Lactose-free milk traditionally has been created by treating conventional or organic fluid milk with the lactase enzyme. Lactaid is among the best known of the lactase-treated milks, and the company also produces lactase enzyme tablets to be taken at the same time as dairy consumption. The introduction of ultrafiltration as a processing option has opened the door for a wider variety of lactose-free milks. The brands fairlife, based in Chicago, and Organic Valley, based in La Farge, Wisconsin, both use ultrafiltration to remove some of the lactose from fluid milk. The ultrafiltration process also concentrates the protein in fluid milk by removing liquid whey. Ultrafiltered milk then is treated with lactase enzyme to convert the remaining lactose into simple sugars. Both brands promote their lactose-free milk as having 50% more protein and 50% less sugar than regular milk. Organic Valley also offers a lactose-free, high-protein milkshake.
Slate, based in Boston, recently introduced its first product line, lactose-free chocolate milk in a shelf-stable can. This product is positioned for adults on the go rather than for children. Slate’s products are ultrafiltered, followed by treatment with lactase. Like other lactose-free chocolate milk producers, Slate sweetens its products with a combination of cane sugar and a nonnutritive sweetener but adds less sugar than many other brands. Slate uses monk fruit, popular for its natural origins; combinations of nonnutritive sweeteners also are common in chocolate milk products.
Self-described dairy disruptor JoeFroyo, based in Upland, California, developed a proprietary process for creating a lactose-free cultured dairy base using high-pressure processing, a cold-pasteurization technology best known for producing bottled fresh juices. The company’s Cold-Pressed Creamery line of cold-pressed dairy products includes milk, probiotic cold brew-cold pressed milk beverages, and a “clean label” creamer.
Yogurt and Kefir
Some people who can’t tolerate lactose-containing liquid milk can consume conventional yogurt without developing symptoms because the live and active cultures in yogurt help break down lactose. In addition, it’s thought that because yogurt travels more slowly than milk through the gastrointestinal tract and since lactic acid bacteria in yogurt survive the stomach’s acidic environment, lactic acid bacteria have adequate time to help digest lactose before and while it passes through the small intestine.3
Lactose-free yogurts typically are made from a base of lactose-free milk. The bacterial cultures used to ferment lactose-free yogurt don’t require lactose to grow and flourish. They can feed on all of the macronutrients in milk, as well as on the simple sugars generated from lactose or added for sweetening.
Some lactose-free yogurts differentiate themselves by starting with a base of strained or ultrafiltered milk, with its concentrated amounts of protein and lower amounts of lactose. Yogurt cultures and lactase then are introduced to remove the remaining lactose. Certain brands add proprietary probiotic strains for specific benefits—for example, digestive health or immune response.
Nevertheless, lactose-free yogurts may or may not be suitable for a low-FODMAP diet, depending on their source of sweetening. “Eliminating lactose gets rid of a major FODMAP source, but products sweetened with agave, honey, fructose, or certain fruits add a different source of FODMAPs and should be avoided by people trying to eliminate FODMAPs,” Scarlata says.
Cheeses
Most hard cheeses are naturally low in lactose. Lactose is found primarily in the whey component of milk and cream, the liquid that’s drained off from curds during the cheese-making process. The curd—sometimes rinsed to remove any remaining whey—eventually is turned into cheese. Any small amount of lactose on the curds is consumed by lactic acid bacteria during the ripening process for making hard cheeses such as parmesan, Swiss, and cheddar.
“Many people don’t realize that all cheddar cheese, for example, is lactose-free as a result of the aging process,” explains Sara Wing, RD, health program director at Cabot Creamery in Waitsfield, Vermont. “Cheeses that undergo a natural aging process contain little to no lactose.”
Softer cheeses such as Brie and cream cheese contain small amounts of lactose. Their lactose content is low enough (1 to 2 g/oz) to be tolerated by many people who are lactose intolerant as long as the cheeses are consumed in small portions. Cottage cheese, in contrast, must be treated to remove lactose because its curds are packaged in milk or a combination of milk and cream; burrata, a cheese that consists of unfermented cream encased in mozzarella, likewise isn’t lactose-free.
Other Dairy Products
Other dairy products have varying amounts of lactose. Ice cream and frozen desserts are made from cream and milk, both of which contain lactose. Their lactose-free counterparts are created by either starting with lactose-free milk and cream or adding lactase to the ice cream mix before freezing. Higher–dairy fat products such as butter and ghee contain less lactose because of their low content of fluid whey. During butter production, whey and most of the water-soluble components in milk, including lactose, are removed, thereby reducing the lactose content in butter to <0.1%.3 Removing milk solids, which have trace amounts of lactose, from butter yields ghee, a lactose-free dairy fat.
New Technology
DuPont recently introduced a new product, Nurica, that splits lactose into glucose and galactose and then connects the two simple sugars to form a nondigestible prebiotic fiber called galacto-oligosaccharide (GOS). GOS has been shown to alleviate symptoms of lactose intolerance while stimulating growth of particular strains of beneficial microorganisms.4
According to a representative from DuPont, Nurica offers a combination of benefits that include lactose reduction, sugar reduction, and GOS fibers that are key prebiotic ingredients in infant formula. “It is possible that GOS and other prebiotics could change the microflora in a way that enhances lactose tolerance for some people,” Scarlata says. “However, it’s important to go slowly. People who have a high concentration of mast cells in their intestine could become more reactive to lactose, as well as GOS and other prebiotics. Also, it’s hard to know which bacteria the lactose and prebiotics are feeding and whether the bacteria are beneficial.”
Nurica hasn’t been launched yet in products in North America but is approved for use in Europe, the Middle East, Africa, and Latin America. It won’t appear in the ingredient list, but the presence of GOS likely will be highlighted.
In the fall of 2019, the start-up Perfect Day launched a limited-edition lactose-free ice cream made from an animal-free dairy protein created through a microflora fermentation process. For protein production, the company adds genes to Trichoderma, a fungus, to enable it to ferment plant sugar into the proteins whey and casein. The fungus doesn’t produce lactose.
Implications for Practice
Public health recommendations continue to cite the importance of consuming three dairy servings per day, including among those who can’t tolerate lactose.5 For people who enjoy dairy but can’t tolerate lactose, products labeled lactose-free can replicate the taste and nutrition benefits of dairy with little or no discomfort.
“When looking for a lactose-free cheese, first look at the label,” Wing advises. “On every Nutrition Facts panel, you’ll find the amount of total sugar in that food. If it says 0 g, that means there’s no sugar, and no sugar means no lactose.”
Because dairy products aren’t culturally significant for all populations, dietetics professionals should tailor their guidance to include lactose-free products and strategies when relevant and provide other sources of calcium and dairy nutrients for non-Western-style diets.
“Each client’s food beliefs, culture, and lifestyle affect their food choices,” says Vandana Sheth, RDN, CDE, FAND, a Los Angeles–based private practitioner, author of My Indian Table: Quick & Tasty Vegetarian Recipes, and spokesperson for the Academy of Nutrition and Dietetics. “When it comes to dairy and dairy products, if a client doesn’t incorporate these and I notice a nutrition gap, I discuss lactose-free products as an option if they would like to try them. Clients who avoid dairy due to a specific belief or lifestyle may find dairy-free alternatives to be more acceptable, or they may prefer to avoid dairy products and dairy alternatives altogether. I always encourage my clients to share their cultural food stories with me so I can better help them meet their nutrition goals with or without lactose-free dairy products.”
— Mindy Hermann, MBA, RDN, is a food and nutrition writer and communications consultant in metropolitan New York.
References
1. Lapides RA, Savaiano DA. Gender, age, race and lactose intolerance: is there evidence to support a differential symptom response? A scoping review. Nutrients. 2018;10(12):1956.
2. Lactose intolerance. Genetics Home Reference website. https://ghr.nlm.nih.gov/condition/lactose-intolerance#statistics. Updated May 2010.
3. Dekker PJT, Koenders D, Bruins MJ. Lactose-free dairy products: market developments, production, nutrition and health benefits. Nutrients. 2019;11(3):E551.
4. Arnold JW, Simpson JB, Roach J, Bruno-Barcena JM, Azcarate-Peril MA. Prebiotics for lactose intolerance: variability in galacto-oligosaccharide utilization by intestinal Lactobacillus rhamnosus. Nutrients. 2018;10(10):E1517.
5. Hodges JK, Cao S, Cladis DP, Weaver CM. Lactose intolerance and bone health: the challenge of ensuring adequate calcium intake. Nutrients. 2019;11(4):E718.