Can Lactose Intolerant People Absorb Calcium From Milk? The Surprising Truth

January 4, 2026 •

4 min read

Did you know that up to 75% of adult African Americans and 90% of Asian Americans are lactose intolerant? Despite this high prevalence, research shows that the inability to digest lactose does not directly prevent lactose intolerant people from absorbing calcium from milk.

Quick Summary

Many believe lactose intolerance automatically impairs calcium absorption from milk, but this is a common misconception for adults. The real threat to bone health stems from the widespread avoidance of dairy, which can lead to insufficient overall calcium intake. Effective nutritional strategies are available to ensure adequate consumption.

Key Points

Lactose and Calcium Absorption: In adults, a deficiency of the lactase enzyme does not directly prevent the absorption of calcium from milk.
The Real Risk Is Avoidance: The primary danger to bone health for lactose intolerant individuals is not poor absorption, but rather the complete avoidance of dairy, which can lead to insufficient overall calcium intake.
Lactose-Free Options Are Effective: Lactose-free dairy products contain the same amount of bioavailable calcium as regular dairy and can be consumed safely.
Non-Dairy Sources Are Plentiful: Many foods, including leafy greens like kale and bok choy, fortified tofu, and canned fish with bones, are excellent non-dairy sources of calcium.
Vitamin D is Crucial: Regardless of the calcium source, sufficient vitamin D is necessary for optimal absorption, and many lactose intolerant individuals may need supplements.
Bone Health Requires Proactivity: Maintaining healthy bones requires a conscious effort to find and incorporate reliable calcium sources into the diet, especially if dairy is limited.

Understanding Lactose Intolerance and Calcium Absorption

Lactose intolerance is a digestive condition caused by a deficiency of the enzyme lactase, which is needed to break down lactose, the sugar found in milk. When undigested lactose reaches the large intestine, it is fermented by bacteria, causing uncomfortable symptoms such as bloating, gas, and diarrhea. This digestive distress is often mistaken as a sign that the body is not absorbing any nutrients, including calcium, from milk products. However, numerous studies reveal that the process of calcium absorption is separate from lactose digestion.

The Science Behind Calcium Bioavailability

Calcium absorption is a complex process that primarily occurs in the small intestine and is influenced by several factors, including vitamin D, the presence of certain proteins, and the overall state of the digestive system. The presence or absence of lactase in the small intestine does not appear to be the limiting factor for calcium uptake in most adults. Research using advanced isotope tracing methods has found similar absorption rates for calcium from milk in both lactase-deficient and lactase-sufficient individuals. In some cases, studies have even shown a slightly higher calcium absorption efficiency in lactose-intolerant subjects. This may be due to the effects of unabsorbed lactose on the gut microbiome, which can create a more favorable environment for mineral absorption.

The Real Risk: Not Absorption, but Avoidance

The main concern for lactose-intolerant individuals regarding bone health is not poor absorption from the milk they do consume, but rather the tendency to avoid dairy products entirely. Dairy is a concentrated and reliable source of bioavailable calcium in many diets, and when it is completely eliminated, overall calcium intake can drop significantly. This decreased intake, especially when paired with low levels of vitamin D, can lead to negative long-term health consequences, such as lower bone mineral density and an increased risk of osteoporosis and fractures. It is crucial for those with lactose intolerance to be proactive about finding alternative calcium sources to compensate for dairy avoidance.

Maintaining Adequate Calcium Intake with Lactose Intolerance

Fortunately, there are several effective strategies for managing calcium intake while minimizing or avoiding lactose-related discomfort. These approaches allow individuals to meet their nutritional needs without sacrificing bone health.

Choose Lactose-Free Dairy: Many supermarkets offer lactose-free versions of milk, yogurt, and cheese. These products are made by adding the lactase enzyme during processing, breaking down the lactose before consumption. They contain the same amount of calcium and other nutrients as their traditional counterparts and are easily digestible for those with an intolerance.
Eat Lower-Lactose Dairy: Certain dairy products are naturally lower in lactose and are often well-tolerated. Aged hard cheeses, such as Swiss or cheddar, contain very little lactose. Yogurt with active bacterial cultures is also an excellent option, as the bacteria help break down the lactose.
Consume Calcium-Fortified Foods: Many non-dairy items are fortified with calcium to help meet dietary needs. Good options include:
- Calcium-fortified orange juice
- Calcium-fortified plant-based milks (soy, almond, rice)
- Calcium-fortified cereals
Incorporate Non-Dairy Sources: A wide variety of whole foods are naturally rich in calcium and can be a vital part of a balanced diet.
- Dark Leafy Greens: Kale, bok choy, and collard greens are excellent sources of calcium.
- Canned Fish with Bones: Sardines and salmon, when consumed with their soft bones, are rich in both calcium and vitamin D.
- Fortified Tofu: Tofu processed with calcium sulfate is a fantastic source of calcium and protein.
- Beans and Legumes: White beans, navy beans, and chickpeas contribute to calcium intake.
- Nuts and Seeds: Almonds, Brazil nuts, and sesame seeds (or tahini) offer significant calcium.
Consider Lactase Supplements: Over-the-counter lactase enzyme drops or tablets can be taken before consuming dairy products to help with digestion and prevent symptoms.

Bioavailability Comparison: Dairy vs. Plant-Based Sources


Source	Bioavailability	Key Considerations
Cow's Milk (Regular)	High (approx. 30-35%)	Contains lactose, which can cause symptoms in intolerant individuals. Excellent source of multiple nutrients, including calcium, protein, and phosphorus.
Cow's Milk (Lactose-Free)	High (comparable to regular milk)	Lactose is pre-digested with lactase. Offers all the same nutrients as regular milk without digestive discomfort.
Fortified Soy Milk	High (comparable to cow's milk if fortified correctly)	Bioavailability is dependent on the fortification mineral (calcium carbonate is absorbed well). Shaking the carton is important to mix settled calcium.
Kale	Very High (approx. 50-60%)	High absorption rate, but requires a larger volume to match the calcium content of a glass of milk. Free from oxalates that inhibit absorption.
Spinach	Low (approx. 5%)	High in calcium but contains oxalates that significantly inhibit absorption, making it a poor source of absorbable calcium.
Tofu (Calcium-Set)	High (approx. 31%)	Absorption is comparable to dairy if prepared with calcium sulfate. Also a great source of protein.

The Role of Vitamin D

Regardless of dietary sources, adequate vitamin D is essential for the body to absorb and utilize calcium effectively. Vitamin D can be obtained through safe sun exposure, certain foods (like fortified dairy and cereals, salmon, and eggs), and supplements. Individuals who avoid fortified dairy or have limited sun exposure should discuss their vitamin D intake with a healthcare professional to determine if supplementation is necessary.

Conclusion

While lactose intolerance causes uncomfortable digestive symptoms, it does not, in itself, prevent adults from absorbing the calcium present in milk. The primary danger to bone health for lactose-intolerant people is the unnecessary avoidance of dairy, leading to an insufficient intake of calcium over time. By utilizing lactose-free dairy options, including a variety of calcium-rich non-dairy foods, and ensuring adequate vitamin D, individuals can effectively manage their condition and maintain strong bones for life. Consulting with a doctor or dietitian is the best course of action to create a personalized nutritional plan. The National Institutes of Health (NIH) provides valuable information on managing nutritional needs for lactose intolerance, underscoring the importance of informed dietary choices.

Frequently Asked Questions

No, for most adults, lactose intolerance does not directly block the body's ability to absorb calcium from milk. Calcium absorption occurs separately from the digestion of lactose, so the calcium is still available to the body.

The biggest risk is the avoidance of dairy products due to intolerance symptoms. This avoidance can lead to an inadequate overall calcium intake, which is the true threat to bone density and health over the long term.

Yes. Lactose-free milk, yogurt, and cheese have the same amount of calcium as their regular dairy counterparts. The lactase enzyme is simply added to break down the lactose, making the product digestible without altering its calcium content.

Excellent non-dairy sources of calcium include leafy green vegetables (kale, collard greens), calcium-fortified tofu and plant-based milks, canned fish with soft bones (sardines, salmon), and certain nuts and seeds.

Vitamin D is crucial for the body to effectively absorb and use calcium. Without enough vitamin D, the body cannot efficiently absorb calcium from any food source, which can lead to weakened bones.

Not necessarily. Many people can meet their calcium needs through lactose-free dairy, lower-lactose options like yogurt, and a variety of non-dairy foods. However, if dietary intake is insufficient, a supplement can be a good option. It is best to consult a doctor or dietitian.

Yes. Many individuals with lactose intolerance can tolerate small amounts of dairy, especially when consumed with other foods. Products naturally lower in lactose, like aged cheeses and yogurt with active cultures, are also often easier to digest.