Across South Asia, the day is punctuated by cups of chai. It accompanies the morning, the afternoon, and very often, the meal. So deeply embedded is this habit that drinking tea after eating feels not just normal but almost necessary. Yet familiarity should not be mistaken for wisdom. When examined closely, the practice of drinking tea — particularly Indian-style chai — close to a meal turns out to be nutritionally problematic, and the case for avoiding it is stronger than most people realise.

Tea, especially black tea, contains compounds called tannins — naturally occurring polyphenols that give tea its characteristic astringency. These tannins have a well-documented tendency to bind with non-heme iron in the digestive tract, forming insoluble complexes that the body cannot absorb. Studies suggest that drinking black tea with or shortly after a meal can reduce non-heme iron absorption by as much as 60 to 70 percent — a significant figure by any measure.

Non-heme iron is the form of iron found in plant-based foods — grains, lentils, leafy vegetables, and spices. Unlike heme iron, which is derived from animal flesh and is absorbed efficiently regardless of what else is consumed, non-heme iron is inherently less bioavailable and is far more susceptible to interference from dietary inhibitors like tannins.

One might reasonably ask: does adding milk to tea not neutralise this effect? To some extent, yes. Milk proteins bind to tannins and reduce their activity. This is why Indian chai, brewed with milk, is somewhat less aggressive in its interference than plain black tea. However, the neutralisation is incomplete. Enough tannin activity remains to meaningfully affect iron absorption, particularly when consumed habitually and in large quantities, as is the norm across much of India.

The Indian Dietary Context is where the concern becomes especially pointed. Indian cuisine, even in its non-vegetarian forms, is overwhelmingly plant-based in composition. A meal of Butter Chicken, for instance, is typically accompanied by tandoori roti/rice along with salads, chutneys and vegetable sides. The chicken itself forms a relatively modest portion of the overall meal. The bulk of what is eaten — the grains, the greens, the legumes, the spices — contributes non-heme iron, not heme iron.

In a purely vegetarian meal, which constitutes the daily diet of a very large proportion of the Indian population, every last milligram of dietary iron is non-heme iron. Lentil dal, spinach, fenugreek, whole wheat roti, and rice are all excellent sources of non-heme iron — but their contribution depends heavily on how well that iron is absorbed. Drinking chai shortly after such a meal actively undermines that absorption.

This is not merely a theoretical concern. Iron deficiency anaemia is one of the most prevalent nutritional disorders in India, affecting women, children, and a significant portion of the general population. While the causes are multiple and complex, habitual post-meal tea consumption — by interfering with iron absorption from predominantly plant-based diets — is a plausible and underappreciated contributing factor.

The solution is neither dramatic nor difficult. Waiting 30 to 60 minutes after a meal before drinking chai preserves all the pleasure of the beverage while allowing the body adequate time to absorb the iron from food without interference. This small adjustment costs nothing and demands no significant change in lifestyle or taste.

The broader lesson here is worth noting. Cultural habits, however widespread and comforting, are not always sound from a health perspective. Chai after meals is a loved tradition, and there is no suggestion that it be abandoned altogether. But the timing matters. What feels like a natural conclusion to a meal may, in nutritional reality, be quietly working against the very nourishment that meal was meant to provide. Awareness of this simple fact is the first step toward a more informed and healthier relationship with one of South Asia’s most cherished beverages.