Green tea, as told over and over again, is a healthier option. If, of course, consumed without sugar, as it is supposed to. But, is it really the safer option?

While, technically, it is, but the packaging might make it harmful for us. As per a November 2024 study published in Chemosphere, researchers tested three different brands of tea bags for exposure of microplastics, which are also degraded plastic bits that do not breakdown and found that it could impact human health.

What were the findings?

The team found that brewing tea in polypropylene, essentially plastic bags, or a common tea bag material actually released over a billion particle per milliliter of tea. In fact, what we think as the paper bags, made of cellulose and mesh nylon bags also shed millions of plastic particle per milliliter.

John Meeker, a professor of Environmental Health Sciences and Global Public Health at the University of Michigan School of Public Health said finding such high amounts of micro and nanoplastics in a product that is supposed to be consumed is a cause of concern.

How was the study conducted?

The researchers first extracted plastics from brewed tea and then exposed them to human intestinal cells that absorbed the plastic particles. It showed that microplastics could remain in the body even after drinking the tea.

The study author Alba Garcia-Rodriguez, a researcher in the Department of Genetics and Microbiology at the Universitat Autonoma de Barcelona said the research calls attention to the path of substantial exposure to plastic particles which are also found in everyday lives. "We have to be concerned about the huge number of single-use plastic that humans are exposed to daily," she said.

How was the test conducted?

Similar tests have been conducted previously. In 2019, a Canadian study was the first one to test nylon and polyethylene tea bags which released 11.6 billion microplastics and 3.1 nanoplastics, measuring less than a micron into a single cup of tea.

In another study from 2023, conducted by Garcia-Redriguez and colleagues, one brand of tea bags were tested that was made of polylactic acid, a biodegradable plant-based plastic. The study showed that it released 1 million nanoplastic particles per tea bag.

For this 2024 study, the research team set broadened their scope by testing out for various materials. They obtained empty tea bags made from three commonly used materials: polypropylene, nylon, and cellulose.

The team simulated typical tea-brewing conditions (without tea leaves) by steeping the bags in sterile water heated to 95°C (203°F) while stirring continuously. They then measured how many plastic particles each material released.

The results revealed that polypropylene bags shed the highest amount of microplastics—approximately 1.2 billion particles. Cellulose paper bags came next, releasing 135 million particles per milliliter, while nylon mesh bags released 8.18 million particles.

The study revealed that hot temperature water exposure and also the stirring of spoon can cause tea bags to "leach plastics".

When the plastics were exposed to humans, it showed that cells absorbed the microplastics, including the mucus cells, as they had the highest uptake of particles. After 24 hours, the particles reached the nucleus of the cells, which houses the DNA.

Health Impacts

Experts find the results concerning, as ingested microplastics could enter the bloodstream after targeting tissues in the gastrointestinal tract, potentially spreading to other organs. While chemicals added during plastic production have been linked to issues like endocrine disruption and cancer, the health effects of ingested microplastics remain unclear. Scientists caution against drawing conclusions, noting that human studies on microplastics are still limited and much more research is needed.

How can one reduce the exposure to plastics? The best way possible is by buying loose leaf, even when you are using green tea, which, is mostly used in tea bags, as a way to make it instantly. In case you are in rush, you can always use the steel infuser to use it as a replacement of plastic tea bags for an instant cup of tea.

If you are considering switching from dairy to plant-based alternatives such as oat and almond milk, a new study warns that the move could increase the risk of nutrient deficiencies, particularly among women and children.

Published in The Lancet Planetary Health, the study found that replacing dairy products with unfortified plant-based alternatives could reduce the intake of essential vitamins and minerals.

“With the growing need to address environmental sustainability, many dietary recommendations are focused on plant-based diets and the reduced intake of animal products,” said Dr Katie Nicol, co-author of the study and Research Fellow at the University of Surrey, UK.

Dr Nicol explained that plant-based alternatives may not provide the same micronutrients as dairy products, putting vulnerable groups such as young children and adolescent females at greater risk of deficiencies that could affect their overall health.

Which Nutrients Could Be Lost When Replacing Dairy?

Also read: Can Eating Peanuts Daily Boost Brain Health And Lower Alzheimer's Disease Risk?

The study warned that replacing dairy products, even partially, with unfortified plant-based alternatives could reduce the intake of four essential micronutrients:

• iodine
• calcium
• riboflavin
• vitamin B12.

In the study, the researchers examined the impact of replacing milk, yoghurt and cheese with commercially available plant-based alternatives on micronutrient intake.

They analysed data from more than 3,500 individuals aged between 18 months and 100 years from the National Diet and Nutrition Survey. Using a modelling technique, they assessed how different levels of dairy replacement affected the intake of these four nutrients.

The findings showed that even modest replacements led to marked declines in all four micronutrients, with iodine intake being particularly affected.

Replacing just 20% to 35% of dairy products with plant-based alternatives, under current market fortification levels, increased iodine inadequacy among adolescent females from 54% to 65%. Among women aged 19–49, it rose from 32% to 42%.

With complete replacement, iodine inadequacy increased to 80% among adolescent females and 72% among adolescent males.

Why Is Iodine Particularly Important?

Read More: Too Much Cow’s Milk Linked To Severe Iron Deficiency In Toddlers, Including Three Deaths

Iodine is essential for producing thyroid hormones, which regulate metabolism and support healthy growth and brain development.

“People may also be unaware of the importance of iodine, which is needed to make thyroid hormones to regulate our metabolism, support healthy growth and brain development,” said lead author Dr Sarah Bath, Associate Professor at the University of Surrey.

She added that iodine is particularly important during pregnancy, when requirements increase, but adequate stores are also needed before pregnancy.

Dairy products are a major source of iodine, while unfortified plant-based alternatives contain very little of the mineral.

Can Fortification Prevent Nutrient Deficiencies?

The researchers also assessed whether mandatory fortification of plant-based dairy alternatives could help prevent nutrient deficiencies.

They found that fortifying these alternatives with essential micronutrients prevented declines in their intake when dairy products were replaced. However, iodine inadequacy remained high, affecting 59% of adolescent females.

The study also found that iodine-fortified bread could further improve iodine intake, reducing inadequacy among adolescent females to 37%.

The findings suggest that combining mandatory fortification of plant-based dairy alternatives with iodine-fortified bread could be the most effective strategy to reduce iodine inadequacy.

Eating about two servings of unsalted, skin-roasted peanuts daily may help support brain health, and reduce the risk of Alzheimer's Disease, suggests a study.

The study, conducted in older adults, suggests that eating 60 grams of peanuts daily for 16 weeks improved insulin responsiveness in brain regions involved in memory, a function that can weaken with age and is linked to Alzheimer's Disease.

Published in the peer-reviewed journal Food & Function, the study highlights how daily peanut consumption may influence brain insulin signalling. However, it does not establish that peanuts can prevent Alzheimer's disease.

How Daily Peanut Consumption Improved Brain Insulin Response

The study included 31 healthy adults aged 60 to 75. During the peanut consumption phase, participants ate 60 grams (approximately two servings) of peanuts daily for 16 weeks.

Researchers used a randomized, controlled crossover trial, allowing them to compare the effects of eating peanuts with those of avoiding them.

The elderly who consumed peanuts daily showed improved insulin responsiveness in several brain regions in the right hemisphere. These included parts of the lingual gyrus, hippocampus, parahippocampal gyrus and posterior cingulate gyrus, all involved in memory-related processes.

While insulin is best known for regulating blood sugar, it also plays an important role in the brain. It supports nerve cell growth, survival and communication, helping maintain memory and other cognitive abilities.

Also read: Just Four Days Of High-Fat Diet May Increase Inflammation, Study Finds

Reduced brain responsiveness to insulin with age has been linked to cognitive decline.

"The hormone insulin plays an important role in the brain, where it supports memory and other cognitive processes. As people age, the brain may become less responsive to insulin, which has been linked to age-related cognitive decline," said Dr Peter Joris, associate professor in the Department of Nutrition and Movement Sciences at Maastricht University Medical Center, Netherlands.

"Our study found that daily peanut consumption beneficially affected insulin responsiveness in memory-related brain regions in older adults. These findings suggest that enhanced regional brain insulin responsiveness may contribute to the cognitive benefits of unsalted, skin-roasted peanut intake," he added.

Which Peanut Nutrients May Support Brain Health?

Read More: Peanut Consumption Associated With Lower Type 2 Diabetes Risk: Study Explains

Researchers supplied participants with premeasured packets of skin-roasted peanuts to ensure consistent consumption.

Participants were instructed to eat their peanuts in the morning or afternoon. They could consume the entire portion at once, divide it into smaller servings throughout the day or include the peanuts in their meals.

Researchers believe several peanut components, rather than a single nutrient, may contribute to the observed effects.

"Multiple nutrients present in peanuts, including unsaturated fats, dietary fibre, vitamins and minerals and bioactive phytochemicals, could potentially contribute to the observed brain benefits," said Joris.

"Peanuts are also a good source of plant-based protein and are especially rich in L-arginine. L-arginine is a key precursor of nitric oxide (NO), which has been reported to facilitate learning and memory performance," he added.

Peanut and Improvements in Blood Flow and Verbal Memory

A previous study published in the peer-reviewed journal Clinical Nutrition 2025, found that consuming peanuts for 16 weeks increased overall cerebral blood flow (CBF) by 3.6% and improved verbal memory performance by 5.8%.

Cerebral blood flow measures the amount of blood circulating through the brain, delivering oxygen and nutrients that brain cells need to function. It is also an indicator of brain blood vessel health.

Long-term diet and obesity are known to affect inflammation. A new study from the University of California, San Francisco suggests that even a few days of eating differently can change how strongly the immune system reacts, at least in mice.

What the researchers did

The study was published in Nature on October 28. It was led by Sagar Bapat, a professor of pathology at UCSF and the paper’s corresponding author. Zewen “Owen” Jiang, who did the work as a graduate student at UCSF, was co-first author, according to UCSF.

The team raised mice on either low-fat or high-fat food pellets. They then applied imiquimod, a cream that triggers skin inflammation, to one ear of each mouse. Mice raised on high-fat food and made obese had severe reactions, while mice on low-fat food had mild ones.

Is it the weight or the diet?

Obesity has long been tied to more severe inflammation, but it wasn’t clear why. “We wanted to know whether it was the extra weight or simply the bad diet that was driving the stronger response,” Jiang said.

To find out, the researchers switched normal-weight mice from low-fat to high-fat food for just four days, then applied the cream three days later. These lean mice developed severe ear inflammation, just like the obese mice. In the other direction, obese mice moved to normal food for four days had much milder inflammation.

The paper’s conclusion is that the dietary state around the time inflammation starts, rather than obesity itself, determines how severe the disease gets.

The skin remembered

Weeks later, the normal-weight mice were back on low-fat food and their inflammation had cleared. The researchers applied the cream again to the same ear. The reaction was far stronger than expected.

The researchers found that high-fat food drew rapid-response immune cells into the skin, which amplified the reaction. As the inflammation faded, memory T cells stayed behind in the ear. Together, these changes left the tissue primed for the next flare-up, UCSF reported. The paper also found that the response depends on CD4+ T cells, and that a protein complex called NLRP3 drives the diet-amplified disease.

The team saw a similar heightened response in the lungs after a few days on a high-fat diet.

Also Read: Psoriasis: Understanding The Skin Condition And Ways To Manage Flare-ups

What the scientists said

“Long-term dietary habits absolutely matter for health, but our study unearthed a much more real-time influence of diet,” Bapat said. “Breakfast, lunch, dinner, they all can have a tremendous and rapid impact on the immune system.”

Jiang added a note of caution. “The diet of a laboratory mouse doesn’t map neatly onto what we eat, but it’s striking how quickly the immune system responds to what’s happening in the body right now,” he said. “Diet, exercise, sleep, they could all shape immune health in ways we don’t yet appreciate.”

What this does and doesn’t mean

This was a study in mice, and the high-fat pellets used in the lab are not the same as human meals. The findings don’t show that a single unhealthy meal will worsen a person’s skin or lung conditions. They do suggest that what is eaten around the time inflammation begins may matter more than researchers had assumed, and that the immune system may hold a memory of it.