Calcium Deficiency

Calcium Deficiency: Signs, Symptoms & Treatment

November 15, 2021

Calcium Requirements and Dietary Sources

What Is Calcium and What Does It Do?

Calcium is classified as a mineral that helps your body form strong bones and teeth but also plays a role in muscle function, nerve transmission, regulating normal heart rhythms, and hormone secretion. About 99% of the body’s calcium is stored in bones, whereas the remaining 1% is found in muscle, blood, and other tissues. (1)

Food sources of calcium include Greek yogurt, cottage cheese, cheese, broccoli, kale, tofu, beans, canned sardines, and soft-shell crab. (2) Contrary to popular belief, milk is not an optimal source of calcium for bariatric patients as it contains simple sugars which can lead to dumping syndrome and/or hinder weight loss.

Although you can get a lot of vitamins and minerals from your diet, it is difficult for weight loss patients to achieve the recommended amount of calcium without supplementation. Supplements are meant to be used to fill in the gaps from what your diet may be lacking.

After bariatric surgery, it is critical to take supplements for life in order to prevent deficiencies from occurring. Bariatric patients are at an increased risk of developing nutrient deficiencies due to the nature of the surgery and how it rearranges your anatomy, decreases your stomach acid, and reduces your capacity for food. (3)

How Much Calcium Should I Supplement With?

After bariatric surgery, the American Society for Metabolic and Bariatric Surgery (ASMBS) recommends taking 1200-1500mg per day of calcium citrate for the sleeve gastrectomy/gastric bypass and 1800-2400mg per day for the duodenal switch. (3,4) Older adults may need additional calcium to protect their bone health and stave off bone diseases that can develop as you age, such as osteopenia and osteoporosis. (5)

5 Key Things to Remember About Taking Calcium: (2, 6)

  1. You may take your calcium supplements with or without meals.
  2. Make sure to choose the form calcium “citrate”. Other forms of calcium require stomach acid for digestion, whereas citrate does not. Being that you have significantly less stomach acid after surgery, citrate is absorbed better. Additionally, the citrate form is protective against the formation of calcium-rich kidney stones.
  3. Calcium supplements should be taken in divided doses of about 500-600mg at least 2 hours apart because your body can only absorb so much at a time.
  4. Do not take your calcium at the same time as your bariatric multivitamin. Why? -- Because calcium and iron compete for absorption. Caffeine can also inhibit calcium absorption.
  5. Consistency is key! Set a reminder on your phone to prompt you to remember to take it three times a day. Missing one dose over the course of the week probably won’t affect you much, but missing one dose 5 times a week may.

Deficiency signs/symptoms:  Some patients have none, but some may experience tingling, fatigue, mood changes, leg cramping, muscle weakness, or even seizures in extreme cases. (1)

Calcium Deficiency

How Do I Know If I Have A Calcium Deficiency?

Since the body is really good at regulating calcium levels, a serum calcium lab value is not a good indicator of whether or not a person is deficient in calcium. This is because when calcium levels drop too low in the blood, parathyroid hormone (PTH) will signal the bones to release calcium into the bloodstream. Therefore, the gold standard lab value to help identify a calcium deficiency is actually an elevated PTH. This may be diagnosed as “secondary hyperparathyroidism”, and the treatment is calcium supplementation. It is important to note that vitamin D helps your body absorb calcium, so if you are deficient in calcium, it is prudent to evaluate vitamin D status as well. (1)

What Will Happen If I Become Calcium Deficient?

Calcium deficiency can lead to diminished bone density, early bone loss, limited mobility, and an increased risk of fractures. Progressive loss of bone mineral density can be identified/assessed by a dual-energy x-ray absorptiometry (DEXA) scan. Being proactive by eating a balanced diet and taking your calcium supplements is your best protection against these long-term consequences. (1,2)

Since we have large reservoirs of calcium stored in our bones, deficiencies can take time to develop.

Following your program’s dietary guidelines and vitamin protocol will significantly reduce your chances of developing deficiencies. Make sure to follow-up with your providers annually, so they can order labs/DEXA scans, identify possible deficiencies, and treat them.

Calcium Deficiency References

  1. Calcium. Harvard School of Public Health - The Nutrition Source. (2020, October 19). Retrieved October 6, 2021, from
  2. Calcium. Linus Pauling Institute. (2021, January 1). Retrieved October 7, 2021, from
  3. Patel, R., & Saumoy, M. (2021, March 23). Treatment of Micronutrient Deficiencies Pre and Post Bariatric Surgery. Current Treatment Options in Gastroenterology.
  4. Parrott, J., Frank, L., Rabena, R., Craggs-Dino, L., Isom, K. A., & Greiman, L. (2017). American Society for Metabolic and Bariatric Surgery Integrated Health Nutritional Guidelines for the surgical weight loss patient 2016 update: Micronutrients. Surgery for Obesity and Related Diseases, 13(5), 727-741.
  5. NIH Osteoporosis and Related Bone Diseases National Resource Center. “Osteoporosis: Peak Bone Mass in Women.” October 2018.
  6. Tarplin, S., Monga, M., & Ganesan, V. (2015, May). Stone Formation and management after Bariatric Surgery. Nature reviews- Urology. Retrieved October 13, 2021, from

Jessica Arroyo, RD, CSOWM is a registered dietitian working for the Bariatric Surgery Clinic at Banner University Medical Center.

Calcium Deficiency
jessica arroyo


Jessica Arroyo, RD, CSOWM is a registered dietitian working for the Bariatric Surgery Clinic  at Banner University Medical Center in Phoenix, Arizona. Jessica earned her Bachelor’s degree through Arizona State University and has over 10 years of experience as a dietitian. She is a certified specialist in Obesity and Weight Management and a member of the Weight Management Dietetic Practice Group through the Academy of Nutrition and Dietetics.