Nickel is a chemical element found in many food items like chocolate, oats, nuts, shellfish, tea, gelatin, and canned fruits and vegetables. The amount of nickel in a food depends on the nickel content in the soil where it was grown. The typical daily dietary intake of nickel is 70–400 μg/d, but diets high in nickel-rich foods can supply more than 900 μg/d.

This metal can also be released from stainless steel pots and pans, especially when cooking acidic foods like tomatoes, lemons, or vinegar. While nickel is not dangerous for someone who is not allergic to it, it can cause problems for those with a sensitivity.

How To Identify Nickel Allergy?

Approximately 8% to 19% of the population in Europe has a nickel allergy. This is usually a reaction to physical touch, like touching a piece of equipment made of nickel. However, other people react to nickel introduced through their diet. Even in low doses, their skin can react in a similar manner, producing contact dermatitis. This includes symptoms like redness, irritation, inflammation, or rashes on the skin.

For some, the reaction goes beyond skin irritation. Symptoms can include headaches, stomachaches, and respiratory symptoms, which are collectively known as Systemic Nickel Allergy Syndrome (SNAS). Doctors have also linked nickel sensitivity to symptoms of fibromyalgia, chronic fatigue, and other chronic diseases. However, for those without sensitivity, moderate levels of nickel in foods are generally safe. It is also recommended to avoid eating nickel-rich foods on an empty stomach, as this can worsen the effects.

Sources Of Nickel

The level of nickel in foods depends on the plant species and the nickel content in the soil. In seafood, it depends on the aquatic environment. Some foods are known to contain more nickel than others. For instance, flour and grains, such as oats, buckwheat, whole wheat, and brown rice, are high in nickel. Seeds like sunflower, sesame, and alfalfa also contain moderate amounts of nickel.

Seafood and shellfish, including shrimp, mussels, and crawfish, are rich in nickel, and certain legumes like chickpeas, lentils, peanuts, and soy products are also high in nickel. Green vegetables such as kale, spinach, lettuce, and cabbage should be avoided or eaten in moderation. Most fruits are safe to eat, but figs, pineapples, prunes, and raspberries are more likely to trigger a reaction. Chocolate, due to its fat content in cocoa, can increase the potential for nickel-related reactions.

If you are reactive to foods containing nickel, your doctor may recommend a low-nickel diet. Alternatives like cornmeal, corn tortillas, and cornflakes are good substitutes for wheat-based foods. Non-seafood meats, such as chicken, beef, and pork, are low in nickel and safe to consume. Most fruits, including pears, apples, strawberries, and grapes, are also suitable for a low-nickel diet. Polished rice and root vegetables like potatoes, carrots, and sweet potatoes contain only trace amounts of nickel, making them safe choices.

Managing a nickel allergy requires awareness of high-nickel foods and suitable alternatives. With a few adjustments, it is possible to maintain a healthy diet while avoiding symptoms.

Receiving a vaccine booster in the same arm as the first dose triggers a faster and stronger immune response and helps the body build protection faster, a new study from Australian scientists has revealed. The findings could help improve vaccine strategies and may eventually lead to vaccines that need fewer boosters. The study was published in the journal Cell and finds that the immune system responds more quickly when both doses are given in the same arm.

Why Will It Work?

Researchers have reasoned that getting jabbed in the same arm works better because immune cells in nearby lymph nodes, which are the body's infection-fighting hubs, become "primed" after the first shot. When the booster arrives in the same spot, these cells spring into action and help produce stronger antibodies. "This is a fundamental discovery in how the immune system organises itself to respond better to external threats," said the study's co-senior author Tri Phan, director of the Precision Immunology Program at the Garvan Institute.

Researchers discovered this effect first in mice, then confirmed it in a clinical study involving 30 people who received the Pfizer COVID-19 vaccine. Those who had both doses in the same arm developed faster and more effective protection, especially against COVID-19 variants like Delta and Omicron. While both groups ended up with similar antibody levels after four weeks, the same-arm group gained protection more quickly, a potential game-changer during pandemic outbreaks.

"If you've had your COVID jabs in different arms, don't worry, our research shows that over time the difference in protection diminishes," said the study's co-senior author, Mee Ling Munier from the Kirby Institute.

How Do Vaccines Work?

The immune system has a wonderful layered system of defences, and when it comes to vaccines, two major defenses are activated. One of them is antibodies, which are proteins in the blood. Then you have something called cell-mediated immunity, which involves cells, usually T lymphocytes. You almost always get both. From a regulatory point of view, you often measure antibodies in people and basically know how effective a vaccine is in a population.

Microplastics pose a danger to the heart. While there is enough evidence to show that they clog arteries and exacerbate the risk of stroke, recent research has found that these teeny particles of plastic can trigger cardiovascular diseases. It is estimated that chemicals in plastic were linked to nearly 350,000 heart disease deaths across the world in 2018. Adding to that, is this study published in the journal eBioMedicine, which estimated that roughly 13 per cent of cardiovascular deaths among 55- to 64-year-olds worldwide that year could be attributed to phthalates.

Where Are Phthalates are esters of phthalic acids, which are added to plastics to increase their flexibility, transparency, durability, and longevity. They are found in personal care products like shampoos and lotions as well as in food containers and packaging. It is also possible to injest them through food, absorb them through skin from products containing them or breathe them from dust.

Some studies have shown an association between phthalates and cardiovascular disease, but there isn’t strong evidence to show that the chemicals directly cause heart issues, said Sung Kyun Park, a professor of epidemiology and environmental sciences at the University of Michigan School of Public Health. However, there is enough evidence that states that phthalates increase the risk of metabolic disorders like obesity and Type 2 diabetes, which can cause cardiovascular disease. One way phthalates may do this is by increasing oxidative stress—cell and tissue damage that happens when there are too many unstable molecules in the body—and by promoting inflammation.

Microplastics: Explained

Microplastics are extremely small particles—often less than five millimetres in size—created when larger pieces of plastic break down. They can enter the human body in multiple ways: through the air we breathe, the food we eat, and even skin contact. An even smaller subset, known as nanoplastics, measures under 1,000 nanometers and is completely invisible to the naked eye. Because of their minuscule size, these particles can infiltrate tissues, organs, and potentially disrupt biological functions.

One Simple Way To Mitigate Risk Of Microplastics

Amid growing concerns about microplastic contamination, especially in drinking water, scientists have been working on practical ways to mitigate exposure. In 2024, a research team from Guangzhou Medical Centre made a breakthrough. They discovered that a common household activity—boiling water—can significantly reduce microplastic content in tap water.

According to the team, combining boiling with basic filtration can remove up to 90% of nanoplastic and microplastic particles (NMPs) from household water. However, the method’s effectiveness varied depending on the type of water used. In areas where tap water contains higher mineral content, commonly referred to as "hard water," the technique proved especially efficient.

The secret lies in limescale. As hard water is heated, it forms limescale—a chalky white substance—which appears to create a sticky layer that traps microplastic fragments. Researchers found this natural process enhanced the removal of plastic particles from water, offering a practical and affordable solution for most households.

While more research is needed to fully understand the long-term health effects of microplastics, early evidence suggests they may be more dangerous than previously thought—especially for cardiovascular health.

Most people do not take neck pain seriously. While it is uncomfortable, people attribute it to lifestyle factors like incorrect sitting posture or looking at their phones for too long. However, extended periods of neck pain could be serious.

Most neck pains do not need to be treated as a serious medical threat, however there is an exception. Harvard Health Publishing explains that there's a rare problem worth knowing about: a tear in one of the blood vessels in your neck. Doctors call this cervical artery dissection. It doesn't happen very often – only to about two people out of every 100,000 each year. However, it's a leading cause of strokes in people younger than 50, which makes it important for awareness.

What Is Cervical Artery Tear?

In your neck, there are two sets of important blood vessels: the carotid arteries and the vertebral arteries. Together, these are called the cervical arteries, and they carry blood to your brain. A cervical artery dissection is when there's a tear in the inner lining of one of these blood vessels.

When a tear happens in a cervical artery, blood can leak in between the layers of the artery wall. This leaking blood can form a blood clot. This clot can either completely block the flow of blood through the artery or break off and travel to an artery in the brain. If either of these things happens, it can cause a stroke, which is a serious medical emergency.

Who Should Be Careful?

Cervical artery tears happen more often in younger adults for a couple of reasons. First, some people are born with weak connective tissue in their bodies, which can make their arteries more likely to tear. For these people, a tear in a neck artery is more likely to happen when they are younger. In older people, strokes are often caused by other things, like the arteries in the brain getting narrow because of fatty buildup. But it's still possible for older people to have cervical artery dissections. One study found that some people diagnosed with this problem were over 60.

The second, and maybe a bigger reason why these artery tears are more common in people under 50 is that younger adults are more likely to do activities that involve neck movements that can sometimes cause a tear. There have been reports of dissections happening after things like heavy weightlifting, dancing with a lot of head movements, and even yoga. If certain yoga poses, like a shoulder stand, aren't done correctly, they can bend the neck too far backwards.

You can also bend your neck too far back when you're getting your hair washed at the sink in a hair salon. Even though it doesn't happen very often, there's even a name for it: "beauty parlor stroke syndrome." To be safe, you can ask your hairdresser for a neck extension, which is a little cushion that supports your head so your neck doesn't have to bend so much.

Watch Out for Unusual Neck Pain

If you have a cervical artery dissection, the neck pain is often different from regular neck pain. It might feel strange, it doesn't go away, and it's often joined by a really bad headache. If the tear is in the carotid artery, the pain might spread along the side of your neck and up towards the outside corner of your eye.

If it's in the vertebral artery, it might feel like something sharp is stuck at the base of your skull. If you have this kind of pain, especially if you also have stroke symptoms like dizziness, seeing double, jerky eye movements, feeling unsteady when you walk, or slurred speech, it's important to get medical help right away.