Coffee, one of the most widely consumed beverages globally, is widely appreciated for its stimulating effects and reported health benefits, such as reduced risk of neurodegenerative diseases and improved cognitive performance. However, there is one aspect that is often overlooked when discussing the impacts of coffee consumption: interference with the absorption of essential minerals. Compounds present in coffee, such as tannins and polyphenols, can impair the bioavailability of nutrients such as iron, calcium and zinc, especially in individuals with deficiencies or low intake of these minerals.
Coffee’s interference in iron absorption
Iron is a vital micronutrient found in foods such as red meat, legumes and dark leafy vegetables, and is essential for the production of haemoglobin and the transport of oxygen. However, drinking coffee can interfere with the absorption of non-haem iron, which is found mainly in plant sources. Studies show that tannins in coffee bind to iron, forming complexes that are not easily absorbed by the intestine. This is especially concerning for vegetarians or people with anaemia, whose iron intake relies heavily on plant sources. While moderate coffee consumption is not a cause for alarm for everyone, those with a tendency towards iron deficiency should be aware of this effect.
Calcium and coffee: a delicate relationship
Calcium, found in foods such as dairy products, sardines and cruciferous vegetables, is another mineral whose absorption can be compromised by coffee consumption. The role of calcium in bone health is indisputable, and studies show that the polyphenols present in coffee can form complexes with calcium, reducing its solubility and, consequently, its bioavailability in the body. This can pose a problem for people who have insufficient calcium intake or who are in risk groups, such as postmenopausal women, who are already more vulnerable to osteoporosis.
Zinc: a silently affected nutrient
Zinc, found in foods such as meat, seafood and nuts, is crucial for several enzyme and immune functions. Coffee can impair the absorption of this mineral in a similar way to iron and calcium, through the formation of insoluble complexes. Although less discussed in the scientific literature compared to iron and calcium, zinc deficiency can also have serious consequences, such as reduced immune function and impaired wound healing.
Recommendations to minimize the impact
Given the evidence that coffee can interfere with the absorption of essential minerals, some practices can be adopted to minimize these negative effects. A simple and practical recommendation is to avoid drinking coffee during or immediately after meals rich in iron, calcium and zinc. Ideally, coffee consumption and meals containing these minerals should be spaced at least one hour apart. For those who already have deficiencies or difficulties in maintaining adequate levels of these nutrients, it may be necessary to consult a nutritionist or health professional to optimize the diet and use of supplements.
The role of the health professional
It is essential that health professionals, especially nutritionists and physicians, be aware of the impact of coffee on mineral absorption, especially in more vulnerable populations, such as the elderly, pregnant women, vegetarians and individuals with specific conditions, such as iron deficiency anemia. Awareness of these effects and appropriate counseling can make a significant difference in long-term health.
Conclusion
While coffee offers many health benefits, its adverse effects on the absorption of essential minerals should not be ignored. Balancing coffee consumption with maintaining adequate levels of nutrients such as iron, calcium and zinc is essential to ensure that the benefits of this popular beverage are not accompanied by nutritional deficiencies. By taking simple measures, such as spacing out coffee consumption in relation to meals, it is possible to mitigate the negative effects and continue to enjoy coffee without compromising your health.
