Does Coffee Deplete Calcium? (Surprising Fact)

Coffee cup

Coffee is one of the most widely loved and consumed caffeinated drinks. It comes with many health benefits and instantly gives you an energy fix.

Coffee contains several complex chemical components that help in several beneficial functions of the body like improving memory and cardiovascular health and lowering the risk of Alzheimer’s or Parkinson’s.

However, too much coffee can bring side effects since caffeine may trigger certain cognitive functions in the body.

Moreover, you may wonder if the caffeine content can deplete essential nutrients and minerals present in your body.

Short Answer: The stimulant caffeine, in coffee, can deplete calcium. This isn’t something to worry about if your intake of caffeine is moderate and you’re getting adequate calcium from your daily meals.

If you’re an avid coffee drinker, you should know how the beverage is affecting the calcium levels in your body and whether it’s something concerning or not.

In the following sections, I will be discussing the effects of coffee on calcium absorption and ways to avoid adverse outcomes.

So, continue your reading!

Why Calcium Is Important for You

Calcium is an important mineral found in foods that is essential for performing several functions in your body.

Some important functions include:

  • Maintaining strong bones
  • Protecting bone mass
  • Facilitating muscle move
  • Helping the nerves in carrying messages between the brain and other body parts
  • Releasing hormones and enzymes

If your body is depleting the calcium in your system due to the ingestion of certain food for a long time, it may lead to osteoporosis, dental changes, cataracts, and even alterations in the nervous system.

What Minerals Are Depleted By Coffee?

Essential minerals such as calcium, iron, magnesium, and B Vitamins can be depleted by coffee due to the presence of caffeine. Caffeine may also impede the process of normal nutrient absorption.

Caffeine is a natural diuretic.

It also affects the absorption of iron. This study shows that coffee can be a potent inhibitor of iron absorption. The polyphenol tannin in coffee is the main reason behind this and as you consume more tannins, you inhibit more of the Fe content through the caffeine.

Here’s a table showing how much iron is lost for every milligram of tannins in coffee:

Tannins in Coffee (mg)Decrease in Iron Absorption

Another mineral-depleted by coffee is magnesium that works with calcium and vitamin D in regulating the phosphate homeostasis to influence the proper growth of muscles and facilitating the muscle contraction-relaxation response.

The metabolism of water-soluble vitamins like B-vitamins is also interfered with by the caffeine content. Lastly, it also works as an inhibitor of vitamin D receptors and may lead to osteoporosis (weakening of the bones).

Do You Lose Calcium When You Drink Coffee?

You lose calcium when you drink coffee because the consumption of caffeine can cause your body to urinate more, resulting in calcium excretion.

A regular cup of coffee contains 70-120 milligrams of caffeine. The average quantity is about 95 milligrams per cup.

The recommended caffeine intake for individuals is 400 milligrams as set by the US Food and Drug Administration.

According to experts from Purdue University, the more calcium is lost through urination, the more of it will be absorbed from other sources. This means that due to caffeine consumption you’ll face adverse effects on the calcium level of the body only if you’re not getting the mineral in proper amounts in the first place.

The amount of calcium lost is about 2-4mg which is negligible compared to the recommended calcium quantity in your diet.

Is Coffee Bad For Your Bones?

Coffee is bad for your bones if you’re ingesting too much caffeine in your body and having an inadequate calcium diet.

There hasn’t been any concrete evidence to prove that caffeine inhibits the strength of the bones but there were several reports regarding the association of reduced bone mass and increased fracture risk with caffeinated drinks.

Caffeine may not directly trigger the risk factors of osteoporosis in healthy individuals. However, in elderly people, especially women, the imbalance of calcium may be heavily impaired due to the heavy dosage of caffeine consumption.

The intake of more than 200-300 milligrams of caffeine per day may accelerate the process of bone loss at the spine of elderly postmenopausal women.

Quick review on the effects of caffeine on your bones.

The Effects Of Coffee On Bone Density

Though there is a lack of observational studies, coffee is related to have the following side effects on bone density:

  • Reduced bone mass
  • Increased risk of hip fracture
  • Negatively influencing calcium retention
  • Reduced bone mineral density

Reviews on animal models suggest that the regular ingestion of caffeine negatively affects the calcium level as it increases calcium excretion. It may impair the efficiency of calcium absorption and limit the roles of vitamin D in bones as well. All these may collectively result to affect the bone mineral density in the long run.

However, no strong data or evidence are present to present a convincing conclusion regarding this and more concrete reports need to be managed.

The caffeine in coffee may reduce the density of the bone.
Caffeine might reduce your bone density.

How Does Caffeine Affect Calcium Absorption?

Caffeine affects calcium absorption in the body by reducing renal reabsorption and intestinal calcium absorption efficiency.

The increase in calcium excretion is very small and the overall change in calcium can be compensated within a few hours.

As already stated above, moderate consumption of coffee will not affect your bone health. The concern lies when you’re already on a low calcium diet that you’re not paying attention to. Most of the implications of caffeine being a risk factor for osteoporosis were observed in populations consuming significantly low amounts of calcium.

High caffeine consumption may reduce inositol levels in the blood that can substantially increase calcium excretion. This will ultimately reduce the calcium absorption in your body.

Remember, low calcium intake is clearly linked with skeletal fragility so to ensure healthier bones you must choose a diet with at least 700-1000 milligrams of calcium a day.

Does Decaf Coffee Stop Calcium Absorption?

The common idea that prevails is that since decaffeinated coffee doesn’t contain caffeine so it might not impede calcium absorption. However, similar to regular coffee, decaf coffee may also reduce caffeine absorption.

Having a decaf drink be it tea or coffee won’t remove the potential of reducing bone density. This is because the decaf drink that you’re having isn’t completely caffeine-free.

It contains caffeine of about 5-30 milligrams and is prepared from Robusta coffee beans. This type of beans is generally more acidic and may cause more depletion of the calcium content. The release of calcium would counteract the increase in the body’s acidity level and lower the body’s pH level.

Thus, having decaffeinated coffee won’t necessarily be of any benefit unless you’re having more alkaline foods in your diet.

Does Adding Milk to Coffee Reduce Calcium?

Adding milk to coffee won’t reduce the mineral as milk is an important source of calcium.

On the contrary, milk can offset calcium loss by caffeine. One cup of milk contains approximately 300 milligrams of calcium.

Milk is a good source of calcium and adding it to coffee offsets the net calcium change.
Adding milk to coffee will offset the calcium loss.

If you feel that the caffeine might affect your calcium absorption then add 1-2 tablespoons of milk to the drink. This will help you in regaining your calcium needs depleted by caffeine.

The amount of calcium added to the coffee through milk will outweigh the negligible calcium loss due to the stimulant. This will also help you in getting a better taste if you don’t like black coffee.

What Should You Do To Avoid The Adverse Outcomes?

You can’t stop the depletion of calcium from the consumption of coffee but the thing that you can do is maintaining a balanced diet to offset the loss of calcium from your body.

For elderly women, a regular calcium source is very much essential for keeping the bone sturdy.

The following tips may help you in avoiding the unwanted health concerns from the calcium deficiency of regular caffeine consumption:

  • Balance your caffeine intake between regular coffee and decaf coffee
  • Use milk instead of water to make the coffee
  • If you’re having tea, go for the hot or decaffeinated one
  • Avoid other caffeine-laden drinks and food
  • Consider taking more alkaline food like fruits and vegetables
  • Switch to a fat-free latte drink occasionally

Most importantly, moderation is the key, and drink your caffeinated drink in limited quantity. If you’re curbing your intake, you may counter withdrawal symptoms at first but it’s better for the long run.


In conclusion, caffeine increases the calcium excretion from your body but the amount is really small.

Within 2-3 hours you’ll get the calcium back so the net effects of calcium change remain unchanged.

Since caffeine is a psychoactive drug, the overall effect it has on calcium is still controversial. Though there have been several associations of caffeine with the increased risk of fractures, osteoporosis, and periodontal disease, no conclusive evidence has been able to prove the consequences yet.

To offset the depletion of calcium by caffeine, the best you can do is to ensure a healthier diet providing adequate calcium in it.

Moreover, don’t worry if you’re already taking care of your diet and consuming a moderate amount of caffeine every day.

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Matt Marshall

As I learn more and more about coffee and coffee products I want to share all my learnings with you here on this website. I hope you find my articles useful and entertaining to read.

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