WARNING: How a diet heavy in fruit vegetables and nuts could lead to FATAL heart infection

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MRSA warning: Having too much manganese in your body can be an issue

A study, published in the journal Cell Host & Microbe, has shown foods rich in manganese may trigger a potentially fatal illness.

People who have excess levels of tissue manganese, for example by taking supplements, may promote the growth of the bacterium Staphylococcus aureus known as staph.

This can switch off the body’s defences against invading germs.

The common bacteria present on the skin of one in three people causes a wide range of infections, from relatively minor skin infections such as boils, to more serious infections of the blood, lungs and heart.

Most infections are caused by a group called Staphylococcus aureus which is antibiotic resistant.

The essential trace element is found in foods such as spinach, shellfish, hazelnuts, pumpkin seeds, beans and tofu and tea.

What is manganese? 

Manganese is a naturally occurring mineral in our bodies in very small amounts – usually found in the kidneys, pancreas, liver, and bones.

It’s true that manganese can help keep a healthy bone structure, bone metabolism, and helping to create essential enzymes for building bones.

However, taking too much in supplement form – or eating too many fruit and vege – can lead to a variety of very dangerous conditions, some of which are fatal. 

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MRSA warning: New research has revealed manganese can lead to heart infections

Manganese is a naturally occurring mineral in our bodies in very small amounts


The findings by researchers at Vanderbilt University Medical Centre in the United States add to the evidence that diet modifies risk for infection.

Professor Eric Skaar said: “The human body does a wonderful job of regulating nutrient levels, and a traditional Western diet has plenty of minerals in it.

“The idea of super-dosing nutrients needs to be given careful consideration.”

The NHS warns taking high doses of manganese for long periods of time might cause muscle pain, nerve damage and other symptoms, such as fatigue and depression.

The Department of Health said most people get enough through a varied and balanced diet and supplements should be limited.

For most people, taking 4mg or less a day was unlikely to cause any harm but for older people, who may be more sensitive to manganese, they should take less than 0.5mg.

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MRSA warning: It is vital to have enough varied fruit and vegetables to stay fit and healthy

The study looked at the impact of dietary manganese on staph infection in a mouse model.

Most of the mice that ate a high manganese diet – about three times more manganese than normal – died after infection with staph.

The animals on the high manganese diet were particularly susceptible to staph infection of the heart, which was a surprise, Prof Skaar said.

The director of the Vanderbilt Institute for Infection, Immunology and Inflammation said: “We know very little about how manganese is moved around and regulated.

“It’s a mystery why high manganese affects staph infection of a single organ.”

It found that excess manganese inactivates a key line of defence against pathogens – the innate immune system’s reactive oxygen burst.

Prof skarr explained normally, in response to staph, “neutrophils pour into the site of infection and blast the bacteria with reactive oxygen species.”

But the excess manganese counters this blast.

The senior author added: “It’s striking that a single dietary change can inactivate one of the most powerful branches of innate immune defence and lead to fatal infection.”

The protein calprotectin, another line of defence, usually acts as a “sponge” to mop up manganese and other metals and keeping nutrients away from pathogens is known as “nutritional immunity.”

Yet for reasons that are not clear, calprotectin is completely ineffective in the high manganese hearts.

Staph is the leading cause of bacterial endocarditis -an infection of the inner lining of the heart chamber and heart valves- and the second most frequent cause of bloodstream infections.

Interestingly, some populations of people have both increased risk for staph infections, particularly endocarditis, and higher than normal levels of tissue manganese,.

These include intravenous drug users, patients with chronic liver disease and patients on long-term intravenous diets.

Further studies are exploring how manganese is transported and regulated in vertebrates and why the heart is particularly susceptible to fatal staph infections when manganese levels are high.

They are also exploring the impact of other nutrient minerals and vitamins on infection.