Calcium – More Than Just Bone Health

When you think of calcium, chances are your first thought is strong bones and teeth. We know calcium as the mineral that strengthens our skeletal system, however, it also plays other roles in the body.

Beyond its well-known role in supporting strong bones and teeth, calcium plays several critical roles in the body such as muscle contraction, nerve function, blood clotting, cell signaling, as well as regulating heart rhythm and blood pressure.

Interestingly, research has also been investigating calcium’s potential role in body composition and weight loss. In this post, we’ll explore how calcium may impact body composition and weight loss —and how you can get enough of it.

Calcium supplementation and weight loss

Calcium supplementation has been studied for its potential effects on body weight, but the evidence is mixed.

A 2016 systematic review and meta-analysis of 33 randomized control trials, published in the American Journal of Clinical Nutrition, found that overall, a clear association between calcium supplementation and weight loss has not been shown.  

Although, when analyzing results from various subgroups, the research did show that calcium supplementation was associated with modest weight loss in individuals with normal BMI and in men, premenopausal women and women >60 years.  The most common dose studied was 1000-1600 mg/day for at least eight weeks.  

The authors noted several limitations to their review with further research still needed to confirm the relation between calcium supplementation and body weight.

Dairy consumption and body composition and body weight

When looking at the research investigating the association between dairy consumption and body composition or body weight, it shows the effects, although not seen in every population, are dependent on the context of the overall diet. 

Research shows dairy consumption can result in modest weight loss, decreased body fat and decreased waist circumference when it’s included in a calorie-restricted diet. However, if dairy foods are added to a diet with no restrictions and participants can eat as much or as often as desired, then body weight may increase and have no effect on body fat or waist circumference.

Therefore, research results suggest overall energy balance is important and substituting some calories for dairy products may result in modest weight loss when combined with an energy-restricted diet. However, adding dairy products to either a neutral energy balance or positive energy balance does not appear to result in weight loss.

Proposed ways calcium may affect body composition

A number of potential mechanisms have been proposed to explain the potential weight-reducing effects of calcium and dairy products.

Research suggests calcium might influence how your body handles fat. Higher calcium intakes have been linked with:

• Increased fat excretion through the feces (calcium binds fatty acids in the intestine)
• Increased fat breakdown within fat cells (a process known as lipolysis)
• Suppressed fat creation (a process known as lipogenesis)

In simple terms, calcium may help keep fat cells from growing too large, while also encouraging the body to burn more fat for energy.

Interestingly, since dairy contains other nutrients beyond calcium, it may be the additional components of dairy products enhancing its effects.  For example, dairy is rich in protein which can help you feel fuller for longer, potentially reducing overall calorie intake. Dairy proteins may also promote satiety hormones and help supress appetite. Furthermore, the bacteria in fermented dairy products (like yogurt) may have additional effects. More well-designed studies investigating the impact of dairy products and its various components on appetite regulation and energy intake are needed.

How much do I need?

Health Canada recommends different daily calcium intakes from food and supplements combined based on age and gender.

Age group	Recommended intake per day (from food and supplements combined)	Safe Upper Limit
Children 1-3 years	700 mg	2500 mg
Children 4-8 years	1000 mg	2500 mg
Children 9-18 years	1300 mg	3000 mg
Adults 19-50 years	1000 mg	2500 mg
Adults 51-70 years Men Women	1000 mg 1200 mg	2000 mg 2000 mg
Adults > 70 years	1200 mg	2000 mg
Pregnancy & Lactation 14-18 years 19-50 years	1300 mg 1000 mg	3000 mg 2500 mg

Source: Institute of Medicine (IOM). Dietary reference intakes for calcium and vitamin D. Washington, DC: The National Academy Press, 2011.

Getting enough calcium

Calcium is found in a variety of foods. While dairy products like milk, yogurt, and cheese are the most well-known sources, you can also boost your calcium intake from a variety of other non-dairy foods, including:

• Calcium fortified plant-based beverages (such as soy, almond, oat)
• Calcium fortified orange juice (check the label for calcium content)
• Leafy greens (like kale and bok choy)
• Tofu
• Canned fish with soft bones (like sardines and salmon)
• Almonds, chia seeds and sesame seeds

Do I need a supplement?

Speak with your doctor, pharmacist or dietitian to determine if a calcium supplement is right for you.

Bottom Line

• Calcium isn’t just about keeping your bones strong. Beyond its well-known role in supporting strong bones and teeth, calcium plays several critical roles in the body such as muscle contraction, nerve function, blood clotting, cell signaling, as well as regulating heart rhythm and blood pressure.

• Calcium may also play a role in body composition and weight loss. Results are mixed and effects are generally modest and variable across individuals. In the context of calorie restriction, dairy intake may help support weight loss, decreased body fat and decreased waist circumference. The effects may be more pronounced when calcium is obtained from dairy products, as other components in dairy (such as proteins, bacteria) could enhance effects.  More research is needed.

• Remember, increased calcium intake alone (via supplements or dairy) is not a magic bullet for weight loss or body composition changes.

• By ensuring you get enough calcium through a balanced diet and healthy lifestyle, you’ll support multiple aspects of your health.