Scientists have found that eating a lot of rice increases the risk of dying from heart disease due to the naturally occurring arsenic in the crop.

Rice is the most widely consumed staple food source for a large part of the world’s population. It has now been confirmed that rice can contribute to prolonged low-level arsenic exposure leading to thousands of avoidable premature deaths per year.

Arsenic is well known acute poison, but it can also contribute to health problems, including cancers and cardiovascular diseases, if consumed at even relatively low concentrations over an extended period of time.

Compared to other staple foods, rice tends to concentrate inorganic arsenic. Across the globe, over three billion people consume rice as their major staple and the inorganic arsenic in that some to give rise to over 50,000 avoidable premature deaths per year has estimated rice.

Meanwhile, a study found Britons in the top 25 per cent of rice consumption are at six per cent increased risk of dying from cardiovascular disease than the bottom quarter.

The chemical gathers naturally in the crop and has repeatedly been linked to illness, dietary-related cancers and liver disease. In serious cases, it can result in death.

A collaborating group of cross-Manchester researchers from The University of Manchester and The University of Salford have published new research exploring the relationship, in England and Wales, between the consumption of rice and cardiovascular diseases caused by arsenic exposure.

Their findings, published in the journal Science of the Total Environment, showed that once corrected for the major factors known to contribute to cardiovascular disease (for example obesity, smoking, age, lack of income, lack of education) there is a significant association between elevated cardiovascular mortality, recorded at a local authority level, and the consumption of inorganic arsenic bearing rice.

Prof. David Polya from The University of Manchester said: “The type of study undertaken, an ecological study, has many limitations, but is a relatively inexpensive way of determining if there is plausible link between increased consumption of inorganic arsenic bearing rice and increased risk of cardiovascular disease.

“The modelled increased risk is around six per cent (with a confidence interval for this figure of two per cent to 11 per cent). The increased risk modelled might also reflect in part a combination of the susceptibility, behaviours and treatment of those communities in England and Wales with relatively high rice diets.”

While more robust types of study are required to confirm the result, given many of the beneficial effects otherwise of eating rice due to its high fibre content, the research team suggest that rather than avoid eating rice, people could consume rice varieties, such as basmati, and different types like polished rice (rather whole grain rice) which are known to typically have lower inorganic arsenic contents. Other positive behaviours would be to eat a balanced variety of staples, not just predominately rice.

Arsenic occurs naturally in the soil and is increased in locations that have used arsenic-based herbicides or water laced with the toxin for irrigation purposes.

Rice is grown under flooded conditions and this draws arsenic out of the soil and into the water, ahead of eventual absorption by the plants.

Rice is particularly vulnerable because arsenic mimics other chemicals the plant absorbed via its root system, allowing the toxin to bypass the plant’s defences.

Rising temperatures caused by global warming could cause the amount of arsenic in rice to triple by the end of the century, a new study warns.

Scientists at the University of Washington in the US grew rice and replicated various temperatures to mimic growing conditions under various global warming projections.

Trials were done at the current normal temperature of 77°F (25°C) as well as 82°F (28°C), 87°F (30.5°C), and 91°F (33°C) to mimic potential climates by 2100. Plants grown in warmer conditions were found to have higher levels of arsenic throughout the plant – including the grains.

MEANWHILE, rice is about the commonest, cheapest and easiest staple food prepared not only by Nigerian households but in most parts of the world as well.

Indeed, statistics from the United Nations Food and Agricultural Organisation (FAO) indicate that half the world’s population eats rice every day, making the staple a major source of nutrition for billions of people.

But recent studies have associated the much-loved staple with rise in chronic and degenerative diseases such as cancer, diabetes, gastrointestinal problems, depression, developmental problems in children, heart disease and nervous system damage.

Most worrisome are lung and bladder cancers.While researchers have found traces of arsenic from old industrial pesticides on rice grains sold globally, a study reported in the journal PLoS ONE, showed rice has 10 times more inorganic arsenic than other foods and the European Food Standards Authority has reported that people who eat a lot of it are exposed to troubling concentrations.

According to the study, the levels of arsenic in rice vary by type, country of production and growing conditions.Generally, brown rice has higher levels because the arsenic is found in the outer coating or bran, which is removed in the milling process to produce white rice.

The study noted that in the short term, the regular consumption of rice could cause gastrointestinal problems, muscle cramping and lesions on the hands and feet.

The researchers observed that the risk of arsenic poisoning is greatest for people who eat rice several times a day, and for infants, whose first solid meals are often rice-based baby food.

In July 2014, the World Health Organisation (WHO) set worldwide guidelines for what it considers to be safe levels of arsenic in rice, suggesting a maximum of 200 microgrammes per kilogramme for white rice and 400 μg kg−1 for brown rice.

Also, scientists have identified rice as one of the staple diets that are genetically modified (GMOs). Others include corn, soy, cotton, papaya (pawpaw), tomatoes, rapeseed, dairy products, potatoes, and peas.

GMOs are accused of causing cancer, destroying the environment and storing up devastating health risks for children. Controversies surround genetically modified organisms on several levels, including ethics, environmental impact, food safety, product labeling, and role in meeting world food requirements, intellectual property and role in industrial agriculture.

An online journal, China Daily, reported potential serious public health and environment problems with genetically modified rice considering its tendency to cause allergic reactions with the concurrent possibility of gene transfers.

Scientists including the American Academy of Environmental Medicine (AAEM) have warned that GMOs pose a serious threat to health, and it is no accident that there can be a correlation between it and adverse health effects.

In fact, the AAEM has advised doctors to tell their patients to avoid GMOs as the introduction of GMOs into the current food supply has correlated with an alarming rise in chronic diseases and food allergies.

It has been shown that eating a diet of white bread and rice could increase the risk of depression in older women, but whole grain foods, roughage and vegetables could reduce it.

According to a study published in The American Journal of Clinical Nutrition, refined foods cause blood sugar levels to spike rapidly – prompting the body to pump out the hormone insulin, which helps break down the sugar. But this process can cause symptoms of depression. The findings could pave the way for depression being treated and prevented using nutrition.

In a study that included data from more than 70,000 post-menopausal women, scientists found a link between refined carbohydrate consumption and depression.

Britain’s leading expert on rice and contamination, Andy Meharg, a professor of plant and soil sciences at Queens University in Belfast, prevented his own children from eating some rice products because of the arsenic levels.

Meharg said the current method for cooking rice, essentially boiling it in a pan until it soaks up all the liquid, binds into place any arsenic contained in the rice and the cooking water.

By contrast, cooking it in a coffee percolator allows the steaming hot water to drip through the rice, washing away contaminants. There was a 57per cent reduction in arsenic with a ratio of 12 parts of water to one of rice and in some cases as much as 85per cent.

Meharg said: “Rice both white and brown are of good nutritional value. Brown rice especially contains E and B vitamins and minerals such as iron, calcium, magnesium, phosphorus, potassium, sodium and zinc.

“White rice is not that good. More so the processed one that is genetically modified has higher levels of toxins.

“Firstly when you cook rice, rinse properly when it is warm before full boiling, and drain out the fluid. This will get rid of some of the toxins.”

Study author Dr. James Gangwisch, of Columbia University, United States, said: “This suggests that dietary interventions could serve as treatments and preventive measures for depression.

“Further study is needed to examine the potential of this novel option for treatment and prevention, and to see if similar results are found in the broader population.”

White refined foods, known as ‘bad carbs’, have also been said to contribute to obesity, low energy levels and insomnia. Different from their healthier counterparts, white carbs start with flour that has been ground and refined by stripping off the outer layer where fibre is found.

This missing fibre could do wonders for the body, helping reduce the risk of type 2 diabetes, lower blood cholesterol and help people feel fuller for longer. Generally, the more refined the grain-based food, the lower the fibre count. By purchasing organic rice, limiting one’s rice intake and eating a balanced diet, however, experts suggest that health issues associated with long-term arsenic consumption can be avoided.