Coffee can reduce calcium absorption due to its caffeine content, which may inhibit calcium uptake in the body, particularly in high amounts.
Many coffee lovers worry about how their daily brew affects calcium levels. Research shows caffeine may slightly reduce calcium absorption, but the effect is minimal when you get enough calcium in your diet. Here’s what science reveals about coffee and bone health.
How Coffee Affects Calcium Absorption
Caffeine impacts calcium in three key ways:
- Reduces intestinal calcium absorption by 4-6 mg per cup of coffee
- Increases calcium excretion through urine
- May interfere with vitamin D receptors that help absorb calcium
However, these effects are small. Just 1-2 tablespoons of milk can offset the calcium loss from one cup of coffee. For those using self-grind coffee makers, adding milk is an easy solution.
The Research on Coffee and Bones
Studies show mixed results:
| Study | Findings |
|---|---|
| Journal of Nutrition (1993) | No effect on 24-hour calcium balance |
| American Journal of Clinical Nutrition (2001) | Small calcium absorption reduction |
| Nutrients (2025) | No bone impact in IBD patients |
According to research published in the American Journal of Clinical Nutrition, the calcium reduction is too small to matter for those meeting daily calcium needs.
Who Should Be Most Concerned?
Certain groups may need to watch coffee intake:
1. Those With Low Calcium Intake
People getting less than 800mg calcium daily may see more impact from coffee’s calcium effects.
2. Postmenopausal Women
Estrogen loss already reduces calcium absorption, making caffeine’s effect more noticeable.
3. Older Adults
Aging decreases calcium absorption efficiency by about 0.2% per year after age 40.
Practical Tips for Coffee Drinkers
Enjoy coffee without worrying about bones:
- Add milk or cream to your coffee
- Space coffee 1 hour before/after calcium-rich meals
- Ensure adequate calcium intake (1000-1200mg daily)
- Consider a coffee maker with frother for milk-based drinks
As noted in Medical News Today, there’s no conclusive evidence that moderate coffee consumption causes osteoporosis in people with proper calcium intake.
The Bottom Line
While caffeine does slightly affect calcium metabolism, the impact is negligible for most healthy adults consuming adequate calcium. The key is maintaining proper calcium intake through diet or supplements if needed. Coffee lovers can enjoy their brew without guilt by following simple precautions.
