Understanding the Risks: Can You Drink Too Much Calcium?

October 25, 2025 •

4 min read

While most people worry about getting enough calcium, studies show that overconsumption, especially from supplements, can pose significant health risks. So, can you drink too much calcium, and what happens when your intake exceeds safe limits?

Quick Summary

Excess calcium intake, particularly from supplements, can lead to hypercalcemia, kidney stones, and other health issues. Recommended daily allowances vary by age, with upper limits defined to prevent toxicity. Balancing dietary sources is key for safe consumption.

Key Points

Hypercalcemia Risks: Consuming too much calcium, often via supplements, can lead to hypercalcemia, a condition with dangerous health consequences.
Symptoms of Overload: Mild symptoms include constipation and fatigue, while severe effects can involve kidney damage, heart arrhythmias, and confusion.
Tolerable Limits: Most adults have a daily calcium Upper Limit (UL) of 2,000–2,500 mg, above which the risk of adverse effects increases.
Supplements Pose Greater Risk: Unlike food sources, supplements can cause a rapid, excessive spike in blood calcium, increasing the risk of negative side effects like kidney stones.
Food First Approach: Aim to meet your calcium needs primarily through diet, which is safer and provides additional nutrients. Diverse food sources like leafy greens, fortified foods, and canned fish are excellent options.
Managing High Levels: If diagnosed with hypercalcemia, treatment may include increased fluid intake, adjusting supplements, and addressing underlying medical conditions under a doctor's supervision.

The Dangers of Excessive Calcium Intake: Hypercalcemia and Other Risks

Yes, it is possible to consume too much calcium, a condition known as hypercalcemia when blood calcium levels become abnormally high. While your body tightly regulates calcium levels, exceeding the tolerable upper intake level (UL) over time can disrupt this balance and lead to a range of mild to severe health problems. It is crucial to understand that getting too much calcium from food sources is rare; most cases of hypercalcemia linked to intake are due to supplement overuse.

Symptoms of Hypercalcemia

Initially, mild hypercalcemia may produce no symptoms, but as levels rise, you might experience a number of signs affecting various body systems.

Digestive system: Gastrointestinal distress is a common early sign, including nausea, vomiting, constipation, and stomach pain.
Kidneys: Excess calcium forces your kidneys to work harder, leading to increased thirst and frequent urination. Over time, this can cause the formation of painful kidney stones and potentially damage kidney function.
Nervous system: High calcium can interfere with brain function, causing symptoms like fatigue, confusion, depression, irritability, and difficulty concentrating. In severe cases, this can progress to disorientation or coma.
Bones and muscles: Counterintuitively, excess blood calcium can weaken bones. The body may leach calcium from the skeleton to regulate blood levels, which can lead to bone pain and muscle weakness.
Cardiovascular system: In rare but serious cases, high calcium levels can disrupt the heart's electrical signals, leading to abnormal heart rhythms (arrhythmia) and other cardiac issues. Observational studies have even linked high calcium supplement intake to an increased risk of cardiovascular disease.

What is the Safe Limit for Calcium Consumption?

The amount of calcium you need varies depending on your age and sex, and it is important to distinguish between the Recommended Dietary Allowance (RDA) and the Tolerable Upper Intake Level (UL).

RDA: The average daily intake level sufficient to meet the nutrient requirements of nearly all healthy individuals.
UL: The maximum daily intake unlikely to cause adverse health effects in almost all individuals in the general population. Prolonged intake above the UL increases the risk of side effects.

For most adults aged 19–50, the RDA is 1,000 mg per day, with a UL of 2,500 mg. For adults over 50, the RDA increases to 1,200 mg for women and 1,000 mg for men, while the UL decreases to 2,000 mg. The best strategy is to meet your RDA primarily through a balanced diet, only supplementing if food intake is insufficient and as advised by a healthcare provider.

Navigating Calcium Intake: Food vs. Supplements

While dietary sources are generally safer and more bioavailable, calcium supplements are a common way for many people to boost their intake. However, supplements carry a greater risk of overconsumption and potential side effects compared to whole foods. Different forms of supplements also have distinct characteristics.

Comparison of Common Calcium Supplements


Feature	Calcium Carbonate	Calcium Citrate	Plant-Based Calcium (e.g., Algae)
Elemental Calcium	High (~40%)	Moderate (~21%)	Moderate (varies)
Absorption	Requires stomach acid; best absorbed with food	Does not require stomach acid; can be taken with or without food	Often highly absorbable with co-factors like magnesium and Vitamin K
Cost	Generally less expensive	Generally more expensive	Can be more expensive
Side Effects	More likely to cause bloating, gas, and constipation	Less likely to cause gastrointestinal side effects	Often gentler on the digestive system
Best For	Individuals with normal stomach acid who take it with meals	Older adults, individuals with low stomach acid, or those with sensitive stomachs	Those seeking a natural source with supporting minerals

Beyond the Glass: A Guide to Food-Sourced Calcium

Meeting your calcium needs through food is the preferred method, as it reduces the risk of excessive intake and provides additional nutrients. Many excellent sources of calcium exist beyond dairy products.

Dairy products: Milk, cheese, and yogurt are well-known, rich sources of calcium.
Leafy green vegetables: Kale, broccoli, Chinese cabbage (bok choy), and turnip greens are high in calcium. Spinach also contains calcium, but its high oxalate content can inhibit absorption.
Canned fish with bones: Sardines and salmon with edible bones are fantastic sources of calcium.
Fortified foods: Look for calcium-fortified orange juice, plant-based milks (soy, almond), and cereals.
Legumes and nuts: Navy beans, white beans, almonds, and edamame contain significant amounts of calcium.

How to Lower High Calcium Levels

If a blood test reveals you have hypercalcemia, your healthcare provider will determine the underlying cause. Treatment depends on the cause and severity. In mild cases, a doctor may advise simple lifestyle changes:

Increase fluid intake: Drinking plenty of water can help your kidneys flush out excess calcium.
Review supplements: Your doctor may advise you to stop taking or reduce the dosage of calcium supplements and calcium-containing antacids.
Adjust medications: Certain medications, like thiazide diuretics, can elevate calcium levels. Your doctor may need to adjust your prescriptions.

For more severe cases, treatment may involve medications like bisphosphonates or calcitonin, or addressing the root cause, such as an overactive parathyroid gland.

Conclusion: Balance is Key

While calcium is vital for strong bones and overall health, moderation is critical. The answer to 'Can you drink too much calcium?' is yes, particularly when relying on supplements that can cause excessive intake. The safest way to ensure proper calcium levels is through a balanced diet rich in diverse food sources. Supplements should be used cautiously and only under medical supervision, respecting the RDA and UL recommendations to prevent the serious health complications associated with hypercalcemia. Strive for balance, listen to your body, and consult a healthcare professional with any concerns about your calcium intake.

Further information on dietary calcium can be found at the National Institutes of Health.

Frequently Asked Questions

The most common causes of high blood calcium (hypercalcemia) are an overactive parathyroid gland or certain types of cancer, not typically from dietary intake alone. However, excessive use of calcium supplements can also contribute.

Drinking a lot of milk or eating many dairy products is not a typical cause of hypercalcemia because the body has mechanisms to regulate calcium from food. The primary risk comes from overdoing supplements.

For most adults aged 19–50, the tolerable upper intake level (UL) is 2,500 mg per day. For those over 50, the UL drops to 2,000 mg per day. Exceeding these amounts increases health risks.

Early or mild symptoms of hypercalcemia often include excessive thirst, frequent urination, fatigue, muscle weakness, and digestive issues like constipation and nausea.

Calcium carbonate is generally cheaper and has a higher concentration of calcium but requires stomach acid for absorption and can cause gas or bloating. Calcium citrate is better absorbed by individuals with low stomach acid and is less likely to cause side effects, but it is more expensive.

Some observational studies have shown a link between excessive calcium from supplements and an increased risk of cardiovascular disease, though research is ongoing and dietary calcium has not shown the same association.

Depending on the cause and severity, a doctor might recommend drinking more fluids, discontinuing calcium supplements, or prescribe medications. The most effective treatment addresses the underlying condition.

Foods rich in fiber and oxalic acid can help reduce calcium absorption. Good hydration is also crucial for flushing excess calcium through the kidneys. Following a diet recommended by your doctor for your specific condition is essential.