Raise your hand if you’ve ever seen a Got Milk? ad.
A lot of you should be nodding or raising your hands, and if you’re not – I feel really old.
The Got Milk Campaign was started in 1993 for the California Milk Processor Board. The ads not only had celebrities donning milk mustaches, but had facts about dairy like highlighting it’s protein content to build strong bones. The purpose of the ads were to encourage milk consumption, which assisted dairy farmers.
There is always bias in a marketing campaign, but this kind of bias in a health campaign can make you question the benefits of product or item being pushed.
So, while many of us grew up with these ads and may have felt compelled to drink milk because of them, do we really understand calcium, what it does for us and where we can find it?
How many people realize that calcium can be found in other foods – not just dairy? Did you know that for better absorption of calcium you need vitamin D too?
Let’s break down what calcium is, what it’s role is, where we can find it and how certain populations may been impacted differently.
What is calcium and what is its role in our bodies?
Calcium is a mineral that can be found in our bones and teeth, but it also helps with muscle contraction, brain function and blood clotting (Marieb and Hoehn, 2016).
There are 206 bones in our bodies that offer support and protection to a number of muscles and organ systems, which means they need to be strong. Adequate calcium paired with vitamin D can prevent bone breakdown (osteoporosis) by osteoclasts. Osteoclasts are bone-resorbing cells found in bone tissue that causes bones to breakdown and release calcium into the body. While consuming calcium won’t completely prevent breaks or fractures, it does decrease the risk.
Aside from contributing to bone density, calcium plays a role in how cells communicate, blood clotting, muscle contraction and nerve function (U.S. National Library of Medicine, 2018).
How much calcium should you consume?
The recommended daily allowance (RDA) for adults aged 19 to 50 is 1,000 mg. For females over 50, it’s recommended to increase calcium to 1,200 mg (Thompson & Manore, 2015). For males over 71, it’s recommended to increase to 1,200 mg. However, research has shown that an adequate amount can vary between 800 mg and 1,200 mg (Shin, & Kim, 2015). Since the research is so varied, you will other areas of the world like the UK that have lower recommendations.
The upper limit is about 2,500 mg for adults up to the age of 50, and 2,000 mg for adults over 50.
Fun fact – humans only absorb about 30% of calcium from food, which means we aren’t absorbing all calcium being consumed, however, this doesn’t mean that you’re not getting an adequate amount (NIH, 2018).
What factors can contribute to varying consumption needs and what populations can be impacted or at risk for low consumption?
Age is a contributing factor to the RDA of calcium, as well as other nutrients. Children need more calcium than older populations because of bone development and growth. The elderly also need more calcium because of the higher risk of osteoporosis from malabsorption in relation to low vitamin D intake (Francis, et al., 1983).
While gender for adults aged 19-50 years old have the same recommendation, women who are very active as well as post-menopausal women may need more calcium to support bone density. Sex hormones help maintain health, however, after menopause women experience decreased estrogen production. Estrogen deficiency is heavily linked to osteoporosis in older women (Marieb & Hoehn, 2016).
- Malabsorption and maldigestion
There’s many interactions that occur to break down and utilize nutrients within the gastrointestinal tract – it’s more than gut bacteria or enzymatic activity. All of these functions are “vulnerable to a multitude of potential disturbances which may lead to global or specific malabsorption syndromes (Keller & Layer, 2014.)” Individuals living with celiac disease, inflammatory bowel disease, Crohn’s disease and diabetes a just to name a few, need to be more mindful of the nutritional profile of their diet, especially since many foods that a healthy functioning person may consume may cause “flare ups” or irritation in these individuals. Conversations with specialists as well as blood work can help create a plan for proper supplementation.
While not all drugs will have an impact on nutrient absorption, there are some that can impact how vitamin D and calcium metabolized. Some drugs interfere with cell communication which impacts how or when different functions or steps in the absorption process occur, which can lead to malabsorption (Grober & Kisters, 2012).
Corticosteroids for a long period of time can lead to bone loss, and the risk may be increased by other behaviors such as alcohol consumption (Picado & Leungo, 1996).
- Individuals with lactose intolerance or a cow’s milk allergy
Milk products have a high amount of calcium that contribute to adequate amounts, however, many Americans are lactose intolerant. The estimates are between 30M and 50M adults, which is a huge range, but it’s also because there are different kinds of lactose intolerance and many may not be aware that they have it. We’ll get into intolerances versus allergies in another post, but just know that lactose intolerance is a digestive disorder due to inadequate amounts of lactase enzyme (U.S. National Library of Medicine, 2018). Individuals with lactose intolerance may still be able to consume small amounts of dairy or specific kinds of dairy without distress, another reason why the estimates are so varied. Certain populations, like Asians as well as African Americans, Ashkenzai Jew, American Indians and Hispanics show high levels of lactose intolerance (U.S. National Library of Medicine, 2018).
What sources can you find calcium in?
Dairy is a great source of calcium and because of the presence of lactose more calcium from dairy is absorbed, but, there are many other sources that may be helpful for those who can’t consume dairy(Thompson & Manore, 2015). Leafy green vegetables like cabbage, kale and broccoli contain calcium as well as some legumes. Below is a list of non-dairy calcium sources:
- Brussels sprouts
- Butternut squash
- Sweet potato
- Chick peas
- Navy beans
- Pinto beans
One thing to remember is that the calcium profile will be drastically less in these sources than in milk, which may lead to inadequate daily amounts over time. Deficits happen over time, but if you do have a concern, I would encourage you to speak with your doctor about how to determine your needs and appropriate protocol to supplement.
Calcium can’t work alone
Vitamin D is a fat-soluble vitamin that helps improve calcium absorption (NIH, 2018). It can be found in foods like salmon and tuna, but an easy way to obtain Vitamin D is through sunlight. Most individuals can meet their Vitamin D needs through sunlight, however, this can vary based on location and time of the year. Living in New England we know that it’s necessary to bundle up for colder months where we don’t see as much sun, which means we may not be getting as much or enough in November versus June.
The standard recommendation for an adult 19-70 is 600 IU, while adults over 70 may need 800 IU.
Should you use supplements?
Supplementation may not be as helpful as we once thought for a few reasons. The potency and quality of the supplement may not high or consistent, which could lead to ingesting something that won’t provide you with what you’re looking for. Research brands about the policies and how they go about testing. Remember, the FDA isn’t authorized to review dietary supplements for safety or effectiveness. It’s up to the brands to determine these before a product goes to market.
Toxicity is more likely to occur through supplementation and looking at creating a diverse diet may be the best route to take for many populations. Recent research has shown adverse cardiovascular events associated with supplementation (Shin and Kim, 2015). I’d advise you to speak with your doctor about supplementation of calcium and Vitamin D to determine if it’s something you require.
Aside from speaking with your doctor about how much your needs for calcium, you can also obtain a DEXA Scan, which is a scanner that utilizes X-rays to determine bone thickness. The DEXA will also be able to give you a reading on body fat, lean muscle mass and placement of both, which may be helpful when creating your health goals.
There are other vitamins and minerals help keep bones strong like Vitamin K, phosphorus, magnesium and fluoride. All of these can be found by creating a balanced diet that incorporates whole foods. There’s a lot to our health that we can’t see, it’s more than the scale or the amount of space we take up.
Francis, R., Peacock, M., Storer, J., Davies, A., Brown, W., & Nordin, B. (1983, October 13). Calcium malabsorption in the elderly: the effect of treatment with oral 25-hydroxyvitamin D3. European Journal of Clinical Investigation, 391-6.
Grober, U., & Kisters, K. (2012). Influence of drugs on vitamin D and calcium metabolism. Dermato Endocrinology, 158-166.
Keller, J., & Layer, P. (2014, June 30). The Pathophysiology of Malabsorption. Viszeralmedizin: Gastrointestinal medicine and Surgery, 150-154.
Marieb, E. N., & Hoehn, K. (2016). Bones and Skeletal Tissues. In E. N. Marieb, & K. Hoehn, Human Anatomy and Physiology (pp. 173-198). New York: Pearson Learning .
NIH. (2017, March 2). Calcium. Retrieved from NIH: https://ods.od.nih.gov/factsheets/Calcium-HealthProfessional/#h3
Picado, C., & Leungo, M. (1996). Corticosteroid-induced bone loss. Prevention and management. Drug Safety, 347-59.
Shin, C. S., & Kim, K. M. (2015). THe Risks and Benefits of Calcium Supplementation. Endocrinology and Metabolism, 27-34.
U.S. National Library of Medicine. (2018, August 2). Calcium in diet. Retrieved from MedlinePlus: Medical Encyclopedia: https://medlineplus.gov/ency/article/002412.htm
U.S. National Library of Medicine. (2018, August 14). Lactose Intolerance. Retrieved from Genetics Home Reference: https://ghr.nlm.nih.gov/condition/lactose-intolerance