Yes, excessive tea consumption, especially green tea, may contribute to B12 deficiency by interfering with its absorption, due to compounds like caffeine and polyphenols, though research is limited and the effect is more pronounced with large amounts or pre-existing deficiencies. Tannins in tea can inhibit B vitamin absorption, and "toast and tea" diets have been linked to B12 deficiency, but tea itself isn't the sole cause, often involving poor diet or underlying absorption issues.
Green tea may interfere with the absorption of certain B vitamins, especially folic acid and vitamin B12, due to its caffeine and polyphenol content. 9 In particular, the catechins in green tea may reduce the body's ability to convert folic acid—the supplemental form of the vitamin—into its biologically active form.
Caffeine is also diuretic which causes you to urinate more frequently, flushing out water-soluble vitamins such as the B-Complex vitamins and Vitamin C. Caffeine significantly reduces the absorption rate of Iron in your intestines - believed to be up to 80%.
The most common cause of vitamin B12 deficiency is inadequate absorption. The following can cause absorption to be inadequate: Overgrowth of bacteria in part of the small intestine. Impaired absorption (malabsorption disorders such as celiac disease or certain pancreatic disorders)
For pregnancy, Vitamin B12 (like cyanocobalamin or hydroxocobalamin) is crucial for fetal brain/nerve development, especially for vegans/vegetarians; most get enough from animal products, but supplements (oral or injections for deficiency) are recommended if dietary intake is low, with doctors advising specific forms and dosages to prevent anemia and neural tube defects, so always consult your healthcare provider.
During pregnancy, ensuring adequate vitamin B12 levels is crucial for fetal development and maternal health. The third trimester is especially significant as the fetus undergoes rapid growth and development, necessitating adequate nutrient transfer from the mother.
Once treatment begins, recovery typically follows this timeline: First Few Days to Weeks: Many people notice an increase in energy and improvement in symptoms like fatigue and weakness within the first week of treatment. 1 to 3 Months: Neurological symptoms, such as tingling or memory issues, often start to improve.
B12 deficiency can trigger specific food cravings, most notably for meat, fish, or eggs, as the body seeks animal-based sources to replenish the vitamin, especially in those on vegetarian/vegan diets or older adults. While cravings for sugary or salty foods can also signal general B-vitamin issues, the distinct urge for protein-rich animal products is a key indicator, but professional testing is crucial for confirmation.
You can develop vitamin B12–deficiency anemia if you do not eat enough food with vitamin B12, such as if you follow a strict vegetarian or vegan diet.
Two large eggs provide a significant portion of your daily Vitamin B12, roughly 1.4 to 2.7 micrograms, depending on size, with almost all of it found in the yolk, contributing around 15-46% of the Daily Value (DV) for adults, making eggs a good source of this essential nutrient for red blood cell formation and nerve function, though absorption from eggs might be lower than meat, notes Healthline, EggInfo, and Australian Eggs.
Drinking large amounts might cause side effects due to the caffeine content. These side effects can range from mild to serious and include headache and irregular heartbeat. Drinking very high amounts of black tea containing more than 10 grams of caffeine is likely unsafe.
“Never squeeze your teabags, as this can make your tea taste bitter due to the release of tannic acids,” explains Angela Pryce, senior tea buyer at Whittard. “Instead lift it out carefully after 3-5 minutes of brewing.” Our expert Dr Bond says five minutes is the optimum time to let your tea brew.
Reasons to Avoid Overconsumption of Tea
Tea interferes with iron absorption and can lead to iron deficiency anemia when consumed in large quantities. The rechallenge effect of green tea on anemia in a middle‐aged man emphasizes the potential causal role of this beverage.
Older adults and people who have had stomach surgery also are at risk because they may not absorb the vitamin as well. People with digestive conditions such as celiac disease and Crohn's disease also are at risk of low vitamin B-12 levels.
You should also make sure to stay clear of caffeine for at least an hour after taking your vitamin B12 supplement, as consuming coffee, tea, or even chocolate soon after taking your supplement may inhibit efficient absorption and promote early excretion.
Some people can develop a vitamin B12 deficiency as a result of not getting enough vitamin B12 from their diet. A diet that includes meat, fish and dairy products usually provides enough vitamin B12, but people who do not regularly eat these foods can become deficient.
Cutaneous manifestations associated with vitamin B12 deficiency are skin hyperpigmentation, vitiligo, angular stomatitis, and hair changes. A diagnosis of vitamin B12 deficiency is often overlooked in its early stages because these signs are not specific to vitamin B12 deficiency alone.
The following groups are among those most likely to be vitamin B12 deficient.
Symptoms include weak muscles, numbness, trouble walking, nausea, weight loss, irritability, fatigue, and increased heart rate.
Organ meats and shellfish are the richest dietary sources, with a 3-ounce (85 g) serving of cooked clams providing approximately 84.1 µg, while beef liver contains about 70.7 µg. Fatty fish, such as trout and salmon, supply 5.4 µg and 4.8 µg per 3-ounce serving, respectively.
Foods or drinks to avoid
Vitamin B12 deficiency can also cause symptoms that affect your brain and nervous system (neurological symptoms), including: numbness. muscle weakness. psychological problems, which can range from mild depression or anxiety, to confusion and dementia.
When will I feel better? Hydroxocobalamin starts to work straight away. However, it may take a few days or weeks before your vitamin B12 levels and symptoms (such as extreme tiredness or lack of energy) start to improve.
The best form of B12 is often considered methylcobalamin, as it's a naturally occurring, active form the body uses immediately, though adenosylcobalamin is also an active form, with a combination often recommended for better results, especially for deficiency or absorption issues, while cyanocobalamin, a cheaper synthetic option, is effective but requires conversion and is less ideal for some. For general supplementation, natural forms like methylcobalamin or adenosylcobalamin are preferred for better retention.