How do lactose intolerant get calcium

As in the case of lactose content in food, lactase deficiency in the consumer appears not to be a limiting factor for calcium absorption. Using an extrinsic tracer, Smith et al.

Using a double-isotope method, Tremaine et al. Interestingly, the lactase deficient participants had a higher calcium absorption efficiency compared to control group. This finding was similar to that by Griessen et al.

These results may stem from either the habitually lower calcium intake of participants with lactose intolerance or the bifidogenic effect of unabsorbed lactose [ 30 ]. They are also advertised as better-for-you alternatives [ 32 ]. However, the bioavailability of these nutrients from non-dairy drinks is largely unknown, except for soy drink, which is the most common milk substitute and the first one to appear as such on the U.

Plant-based drinks contain higher levels of calcium and zinc absorption inhibitors, such as phytate and oxalate. In general, calcium absorption is inversely proportional to the content of these compounds. However, soy beans, despite being rich in both phytates and oxalates, show relatively high calcium bioavailability. However, a study that employed a single isotope method to measure calcium absorption at a lower dose of calcium 44 mg vs.

The discrepancy may be explained by changes in absorbability due to bacterial fermentation in the lower gut, which requires a longer study period for detection. Another type of beverage frequently investigated for calcium bioavailability is calcium-fortified orange juice. The absorption of calcium was also compared between two fortification methods of orange juice: calcium citrate malate and a combination of tricalcium phosphate and calcium lactate [ 41 ].

The investigators found that calcium citrate malate was superior in terms of calcium bioavailability. These findings indicate that calcium absorption depends not only on the physical formulation of the product and the experimental design length of time over which absorption is measured but also the fortification method.

Therefore, equivalent calcium contents on a nutritional label do not guarantee equivalent nutritional value [ 41 ]. Bioavailability must be measured directly using standardized and generalizable methods [ 42 ]. To date, there are no data on the bioavailability of calcium from plant-based drinks other than soy drink, despite their increasing popularity.

Nor is there any knowledge about the bioavailability of other bone-related nutrients, such as protein. Most plant-based beverages, except soy drink, are 5—10 times lower in protein [ 32 , 35 ].

Protein is important for bone because it enhances insulin-like growth factor 1 that exerts positive activity on skeletal development and bone formation [ 43 ]. A continuous supply of protein is also required for optimal bone remodeling to provide the amino-acids that were removed during bone resorption [ 44 ]. A recent summary of meta-analyses suggests that dietary protein is just as important as adequate calcium intake in reducing bone loss and the risk of hip fracture [ 45 ].

The contents of other nutrients important to bone, including potassium, phosphorus, and magnesium, vary from one plant-based drink to another.

As in the case of calcium, the bioavailability of these nutrients from plant-based drinks has not been established. Nutrient composition of test beverages [ 18 ]. Despite the increasing popularity of plant-based beverages, a considerable gap in knowledge also exists with regard to their impact on bone mineral content BMC and the risk of fracture. Similar to research on calcium bioavailability, most studies examining bone health focused on soy drink.

A study by Gui et al. On the other hand, the association between soy milk versus dairy milk consumption and the risk of osteoporosis was no different in postmenopausal white women [ 47 ]. However, bone density in this study was assessed in heel bone only, which may explain the discrepancy in findings. The effects may also differ depending on the age of the target population. In a longitudinal study of healthy infants, Andres et al. However, since the majority of lactase deficiencies in infants are transient and due to diarrhea, the use of low-lactose or lactose-free formulas has no clinical advantage, except in severely undernourished infants with diarrhea, in whom lactose-free formula may be advantageous [ 49 ].

The in vivo effects of lactose on calcium absorption, bone growth, and BMC were extensively investigated in the s and s. Lactose was shown to enhance calcium bioavailability from a variety of sources at different life stages of development [ 50 , 51 ]. There are two pathways of calcium transport considered in the mechanism of lactose-promoted calcium absorption: passive transport through all segments of the small intestine and facilitated diffusion in the jejunum.

It has been reported that lactose enhanced calcium absorption by increasing calcium permeability in small intestinal villi [ 51 ] and lowering the ileal pH in rats [ 52 ]. In addition to calcium absorption, lactose, together with calcium, significantly improved recalcification of bones in calcium-deficient rats [ 53 ]. Although Shortt et al. Moreover, in two trials using post-weaning rats and swine conducted by Moser et al. However, in the post-weaning rat model, higher levels of lactose in the diet corresponded to increased skeletal calcium content.

Numerous studies demonstrate that dietary lactose facilitates intestinal calcium absorption and promotes skeletal growth independent of the vitamin D endocrine system. Miller et al. The changes observed in the lactose-supplemented group were similar to the vitamin D-replete group. Similar results were reported by Au et al. In addition to pure lactose, milk containing lactose also exerted a better bone protective effect when compared to lactose-hydrolyzed milk [ 59 ] or calcium carbonate [ 60 ].

It has been reported that weanling male rats fed the untreated milk for 28 days absorbed calcium more efficiently and showed reduced urinary calcium loss compared to the rats fed with lactose-hydrolyzed milk.

Moreover, the rats fed with unhydrolyzed milk or supplemental lactose retained more magnesium and zinc in bone [ 59 ]. Weaver et al. In addition, rats fed with nonfat dry milk during growth retained higher bone density and strength in adulthood when the diets were switched to the same low calcium diet compared to rats fed with calcium carbonate. Lactose maldigestion, when combined with inadequate calcium intake, has been suggested as a risk factor for impaired bone health.

Multiple observational studies show that consumers who avoid milk have lower BMD compared to individuals with higher milk consumption. This association is particularly evident in children [ 61 , 62 , 63 , 64 , 65 ].

Observational and longitudinal studies conducted in Europe [ 63 ], Asia [ 66 ], and New Zealand [ 64 ] demonstrated that children with lactose-free or low lactose diets had reduced BMC and BMD. Another study of early pubertal girls in California and Indiana found that perceived milk intolerance was inversely associated with BMC of several bone sites [ 67 ].

A meta-analysis of trials of dairy products and dietary calcium on BMC in children showed significantly higher total body and lumbar spine BMC in groups with higher compared to low calcium intakes [ 61 ]. Several randomized controlled trials also found that increasing lactose intake through a dairy intervention in children resulted in improved BMC, particularly in girls with low baseline calcium intake [ 65 , 68 , 69 , 70 ]. In adolescents, a study by Baldan et al.

In adults, BMD was found to be lower with lactose maldigestion and lower dairy intakes [ 71 , 72 , 73 ]. A recently published population-based study of elderly men and women also found a weak but significant positive association between dairy product consumption and bone properties [ 74 ]. However, inconsistencies in adjustment for confounders and the varying magnitude of association found in previous studies preclude firm conclusions [ 65 , 75 , 76 , 77 , 78 , 79 ].

Whether low dairy consumption also leads to higher rates of bone fracture is a subject of ongoing controversy [ 80 ]. Three observational studies of adult women showed a significant increase in the risk of fracture with low dairy intake [ 65 , 75 , 81 , 82 ]. One population-based study of Finnish elderly adults, which defined lactose intolerance on the basis of a single nucleotide polymorphism of the lactase gene CC genotype associated with reduced dairy intake, found that those with CC genotype had over 3-fold increase in the odds of hip fracture and nearly a 2-fold increase in the odds of wrist fracture compared to the TT genotype [ 83 ].

This association did not hold true in the Finnish postmenopausal women [ 84 ]; however, women in the maldigester group were more frequent users of calcium supplements. Since the publication of the National Institutes of Health NIH Consensus Statement on Lactose Intolerance in [ 65 , 85 ], a meta-analysis of data from 12 cohort studies reported no overall association between milk intake and hip fractures [ 86 ] and two subsequent cohort studies reported either no association in elderly Europeans [ 87 ] or a non-significant lower risk in U.

However, a recently published analysis of two U. These findings suggest that the association between dairy intake and bone fracture risk is positive but relatively small and dependent on factors that vary with the population of interest. With regard to the fracture risk in children, two studies reported that children who avoid milk for more than 4 months had increased risk of bone fractures [ 44 , 62 , 65 ].

This effect may persist into adulthood as a retrospective study of postmenopausal women in NHANES III found that low milk intake during childhood doubled the risk of fracture in later years [ 89 ]. However, a more recently published cohort study of 96, postmenopausal women and elderly men found no association between milk consumption during teenage years and subsequent risk of hip fracture [ 90 ]. Researchers estimate that approximately one-third to one-fifth of individuals with limited lactase activity will have digestive symptoms [ 92 ].

Nicklas et al. Moreover, many of the individuals who do report symptoms show no evidence of lactose malabsorption when tested using objective methods.

Suarez et al. Of these subjects, 21 were lactose maldigesters based on breath hydrogen test of 15 g of lactose, while 9 were lactose digesters. These findings suggest that people who identify themselves as lactose-intolerant may mistakenly attribute abdominal symptoms to milk intolerance.

The NIH consensus panel encouraged health practitioners to diagnose their patients using standardized testing, such as the hydrogen breath test [ 65 ]. Most adults and adolescents with limited lactose digestion can tolerate at least 12 g of lactose, the amount of lactose normally found in 1 cup mL of milk [ 65 ].

The corresponding level of tolerance has not been defined for children. Furthermore, research findings suggest that larger amounts may be consumed by all ages if introduced gradually over a period of 2—3 weeks, due to colonic adaptation. Repeated consumption of lactose favors the development of colonic bacteria that can digest lactose for the host which diminished the symptoms [ 93 , 96 ]. When building lactose tolerance, it is also recommended to consume milk with other foods or as part of a meal, which slows down gastric emptying, reduces the load of lactose that enters the intestine at any time, and allows more time for bacteria to digest lactose [ 93 ].

Another dietary strategy to achieve the recommended 3 serving of dairy is to select aged cheese, which is essentially lactose free, and yogurt with active cultures, which aid in lactose digestion [ 97 ]. Dietary Guidelines for Americans also recommend choosing lactose-reduced or lactose-free milk and fortified soy beverages soymilk as alternatives [ 91 ].

Low dairy diets are frequently inadequate in calcium and a wide spectrum of other nutrients present in milk. A number of studies have indicated that excluding dairy from diet is associated with nutritional deficiencies and reduced BMD [ 71 , 72 , 73 , 93 ]. On the other hand, adequate intake of dairy is a marker of high dietary quality [ 93 , 99 ] and a correlate of lower risks of osteoporosis, hypertension, diabetes, colorectal cancer, and weight gain [ 93 , 98 , , , , ].

Children and adolescents with maldigestion should especially be encouraged to maintain dairy food intake to meet the needs of skeletal growth and to optimize peak bone mass, most of which is attained before the age of 16 [ ]. Children who avoid milk ingest less-than-recommended amounts of calcium and may be at increased risk for deficient bone accretion [ 78 , ].

Cases of severe rickets due to vitamin D deficiency have been described in children who do not consume dairy [ ]. In their statement on lactose intolerance in infants, children, and adolescents, the American Association of Pediatrics stated that restriction of milk and other dairy products is not usually necessary given the available approaches to lactose intolerance [ ]. Portions of 4—8 oz. Dairy consumption should also be maintained during adulthood and in the elderly.

The prevalence of lactose malabsorption increases with age but symptoms of intolerance reported by individuals with malabsorption decrease over time [ 97 ]. Therefore, the elderly should be encouraged to consume dairy foods, especially given their reduced capacity to absorb calcium, to protect them from nutritional deficiencies and to reduce age-related bone loss [ ]. The choice not to exclude children and racial or ethnic minorities from the general 3-serving dairy recommendation was motivated by the high risk of nutrient deficiencies in these groups.

In its consensus statement, the National Medical Association NMA , which represents the interests of African-American physicians and their patients, urged its constituents to follow the same guidelines as the general public, i.

The NMA rationalized their opinion stating that the diets of low-income African-Americans are more likely to be deficient in key nutrients that are easily sourced from milk and dairy and that low intake of these nutrients predisposes Blacks and Hispanics to a higher risk of chronic diseases. The European Food Safety Authority Panel on Dietetic Products, Nutrition, and Allergies also emphasized the need for objective testing before recommending a low-lactose diet and the intake of lactose-reduced and lactose-free products to avoid calcium, vitamin D, and riboflavin deficiencies [ ].

The NIH consensus panel acknowledged that the task of developing a general, evidence-based recommendation for the American public is difficult due to individual differences among lactose maldigesters that include absorptive capacity, intestinal transit times, gut microbiome composition, and sensitivity to symptoms [ 65 ].

Difficulty also arises from the heterogeneity of the available research and lack of a standardized method for diagnosing and reporting symptoms, especially in double-blind randomized controlled trials. The NIH panel stressed the urgent need for future studies to investigate the association between dairy intake and health outcomes in people with lactose intolerance, especially children, the elderly, members of racial and ethnic subgroups, and those with susceptible genetic polymorphisms.

Lactose intolerance has little direct influence on the absorbability of calcium in adult men and women, although additional studies in different age groups are required to reach a firm conclusion. Lactose intolerance may predispose individuals to suboptimal bone health, osteoporosis, and fragility fractures when accompanied by decreased intake or avoidance of dairy.

The current recommendation for individuals with diagnosed lactose maldigestion is to consume 3 servings of dairy per day together with other foods and to opt for dairy products low in lactose, such as aged cheese and cultured yogurt. All authors approved the final version of the manuscript. National Center for Biotechnology Information , U. Journal List Nutrients v. Published online Mar Joanna K. Cladis , and Connie M. Author information Article notes Copyright and License information Disclaimer.

Received Mar 1; Accepted Mar This article has been cited by other articles in PMC. Abstract Calcium is an important nutrient with impact upon many biological systems, most notably bone. Keywords: bone, calcium, lactose intolerance, osteoporosis. Bone Health throughout the Life Span Bone is a dynamic tissue that is constantly changing throughout the lifetime. Open in a separate window.

Figure 1. Calcium Requirements The primary nutrient of interest in bone health is calcium. Dietary Sources of Calcium To meet the calcium recommendations set forth by NAM, consuming a variety of calcium-rich foods each day is necessary. Table 2 Calcium content of dairy products and dairy substitutes [ 18 ]. Table 3 Non-dairy sources of calcium in the diet [ 18 ]. Lactose Intolerance and Calcium Bioavailability from Dairy and Alternative Sources The majority of calcium absorption studies show that neither dietary lactose nor lactase deficiency in healthy adults has a significant impact on calcium absorption.

Table 4 Nutrient composition of test beverages [ 18 ]. Human Studies of Lactose Intolerance, Dairy Avoidance, and Bone Health Lactose maldigestion, when combined with inadequate calcium intake, has been suggested as a risk factor for impaired bone health.

The Majority of People with Lactose Malabsorption Do Not Have Clinical Lactose Intolerance Researchers estimate that approximately one-third to one-fifth of individuals with limited lactase activity will have digestive symptoms [ 92 ].

Lactose Intolerance Need Not Be an Obstacle to Meeting the Need for Calcium with 3 Servings of Milk and Dairy Products Most adults and adolescents with limited lactose digestion can tolerate at least 12 g of lactose, the amount of lactose normally found in 1 cup mL of milk [ 65 ]. Conclusions Lactose intolerance has little direct influence on the absorbability of calcium in adult men and women, although additional studies in different age groups are required to reach a firm conclusion.

Author Contributions J. Funding This research received no external funding. Conflicts of Interest The authors declare no conflict of interest. References 1. Singer A. We usually associate high-calcium foods with dairy products, like milk, cheese, and yogurt.

If you cannot tolerate these foods from a digestive standpoint, you can still meet your calcium requirement by increasing your consumption of certain green leafy vegetables and calcium-fortified foods.

The average man's daily diet should include 1, milligrams mg of calcium, which is the equivalent of three to four servings of high-calcium foods. Some studies suggest calcium supplements may increase the risk of kidney stones or heart disease, so food is the best approach.

Dark green leafy vegetables are excellent sources of calcium and also include many essential vitamins. Collard greens top the list with about mg of calcium per cup, while the trendy kale and its companion Swiss chard contain about mg per cup. However, only a serious salad lover can meet the daily requirement with these foods alone. Fortunately, a variety of foods are now fortified with calcium. Almond milk is typically fortified with calcium and also can offer as much as cow's milk, and soy milk serves up about 60 mg per cup.

As a service to our readers, Harvard Health Publishing provides access to our library of archived content. Please note the date of last review or update on all articles. No content on this site, regardless of date, should ever be used as a substitute for direct medical advice from your doctor or other qualified clinician. Thanks for visiting. Plain yogurt has approximately to milligrams of calcium per cup. Kefir, another type of fermented dairy, supplies a similar amount of calcium. If you still experience side effects with commercially prepared fermented dairy, make your own yogurt and kefir at home, and let it ferment for 24 hours to allow the bacteria to pre-digest the lactose for you.

Cheese is made from milk and therefore contains a significant amount of calcium. If you are lactose intolerant, opt for aged cheeses such as Brie, blue cheese, Cheddar or Parmesan. The increased fermentation time reduces their lactose content to very low levels. Other dairy products, such as cream and butter, are mostly made of milk fat and do not contain lactose, making them safe to eat for people with lactose intolerance.

However, these high-fat dairy products do not constitute a significant source of calcium. Cow milk is a well-known source of calcium and one of the best options to get enough calcium. Skim milk has approximately milligrams per cup, while partially skimmed milk has about to milligrams per cup.