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Fish diet lowers risk of stroke

Fish diet lowers risk of stroke
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Women who eat more than three servings of fish per week are less likely to experience a stroke, a new study suggests. Specifically, fish-lovers in Sweden were 16 percent less likely to experience a stroke over a 10-year-period, relative to women who ate fish less than once a week. “Fish consumption in many countries, including the U.S., is far too low, and increased fish consumption would likely result in substantial benefits in the population,” said Dr. Dariush Mozaffarian of the Harvard School of Public Health. When choosing fish to eat, it’s best to opt for fish that are rich in omega-3 fatty acids, found most abundantly in fatty fish like salmon, mackerel and albacore tuna. “But any fish is better than none,” Mozaffarian noted.

 

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“Indeed, these fatty acids likely underlie the benefits of fish on stroke risk”, said study author Dr. Susanna Larsson of the Karolinska Institute in Stockholm. “These fatty acids may reduce the risk of stroke by reducing blood pressure and blood (fat) concentrations.”

This is not the first study to suggest that people who eat more fish have a lower risk of stroke, and experts already recommend a fishy diet to reduce the risk of cardiovascular problems, Mozaffarian added. “This study supports current recommendations.” Earlier this year, for instance, a study showed that middle-aged and older men who eat fish every day are less likely than infrequent fish eaters to develop a suite of risk factors for heart disease, diabetes and stroke.

In the current study, published in the American Journal of Clinical Nutrition, Larsson and her colleagues looked at 34,670 women 49 to 83 years old. All were free of cardiovascular disease and cancer at the beginning of the study, in 1997. During 10 years of follow-up, 1,680 of the women (4 percent) had a stroke. Stroke caused by blockage of an artery that supplies blood to the brain — also known as a “cerebral infarction” or “ischemic stroke” — was the most common event, representing 78 percent of all strokes in the study. Other types of strokes were due to bleeding in the brain, or unspecified causes.

Women who ate more than three servings of fish per week had a 16 percent lower risk of stroke than women who ate less than one serving a week. “Not a small effect,” Mozaffarian said, noting that it was roughly equivalent to the effect of statin drugs on stroke risk. Furthermore, the researchers asked women about their diets only once, using a questionnaire, which might have caused errors that would underestimate the link between a fishy diet and stroke risk, he explained. “So, the true risk reduction may be larger.”

Interestingly, women appeared to benefit most from eating lean fish, when other research shows fatty fish is better for health. This finding may stem from the fact that most fatty fish, such as herring and salmon, is eaten salted in Sweden, Larsson explained. “A high intake of salt increases blood pressure and thus may increase the risk of stroke,” she said. “So the protective effects of fatty acids in fatty fish may be attenuated because of the salt.”

Indeed, when it comes to fish, not all have equal benefits, Mozaffarian noted – for instance, he said, research has not shown any cardiovascular benefits from eating fast food fish burgers or fish sticks. In addition, women of childbearing age should avoid certain types of fish known to carry relatively high levels of pollutants, such as shark and swordfish, Mozaffarian cautioned. “This is a very, very short list of fish to avoid or minimize — there are many, many other types of fish to consume,” he said. “Women at risk of stroke are generally beyond their child-bearing years, and so for these women, all types of fish can be consumed.”

Larsson and her team speculate that certain nutrients in fish, such as fatty acids and vitamin D, might explain its apparent benefits. The Swedish study cannot prove cause and effect for high fish consumption and lowered stroke risk, however. For instance, fish consumption could be a sign of a generally healthier lifestyle or some other mechanism at work. Last December, Larsson and colleagues published data from the same group of women in the journal Stroke showing that those who eat a lot of red meat may also be putting themselves at increased risk of stroke.

SOURCE: bit.ly/dKunk8 American Journal of Clinical Nutrition, online December 29, 2010.

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New Evidence for Eye-Protective Effects of Omega-3-Rich Fish, Shellfish

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Researchers at Wilmer Eye Institute, Johns Hopkins School of Medicine, wanted to know how the risk of age-related macular degeneration (AMD) would be affected in a population of older people who regularly ate fish and seafood, since some varieties are good sources of omega-3 fatty acids. A diet rich in omega-3s probably protects against advanced AMD, the leading cause of blindness in whites in the United States, according to the Age-Related Eye Disease Study (AREDS) and other recent studies. High concentrations of omega-3s have been found in the eye's retina, and evidence is mounting that the nutrient may be essential to eye health. The new research, led by Sheila K. West, PhD, was part of the Salisbury Eye Evaluation (SEE) study.

Food intake information with details on fish and shellfish consumed was collected over one year using a validated questionnaire for 2,391 participants aged 65 to 84 years who lived along Maryland's Eastern Shore. After dietary assessment was complete, participants were evaluated for AMD. Those with no AMD were classified as controls (1,942 persons), 227 had early AMD, 153 had intermediate-stage disease, and 68 had advanced AMD. In the advanced AMD group, the macular area of the retina exhibited either neovascularization (abnormal blood vessel growth and bleeding) or a condition called geographic atrophy. Both conditions can result in blindness or severe vision loss.

“Our study corroborates earlier findings that eating omega-3-rich fish and shellfish may protect against advanced AMD.” Dr. West said. “While participants in all groups, including controls, averaged at least one serving of fish or shellfish per week, those who had advanced AMD were significantly less likely to consume high omega-3 fish and seafood,” she said.

The study also looked at whether dietary zinc from crab and oyster consumption impacted advanced AMD risk, but no significant relationship was found. Zinc is also considered protective against AMD and is included in an AMD-vitamin/nutrient supplement developed from the AREDS study. Dr. West speculated that her study found no effect because the levels of zinc obtained from seafood/fish were low compared to supplement levels.

The research is published in the December issue of Ophthalmology, the journal of the American Academy of Ophthalmology.

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Can Omega-3 foods prevent eye disease in seniors?

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Eating a diet rich in omega-3 fatty acids appears to protect seniors against the onset of a serious eye disease known as age-related macular degeneration (AMD), a new analysis indicates.”Our study corroborates earlier findings that eating omega-3-rich fish and shellfish may protect against advanced AMD,” study lead author Sheila K. West, of the Wilmer Eye Institute at Johns Hopkins School of Medicine in Baltimore, said in a news release from the American Academy of Ophthalmology.

“While participants in all groups, including controls, averaged at least one serving of fish or shellfish per week, those who had advanced AMD were significantly less likely to consume high omega-3 fish and seafood,” she added.

The observations are published in the December issue of Ophthalmology.

West and her colleagues based their findings on a fresh analysis of a one-year dietary survey conducted in the early 1990s. The poll involved nearly 2,400 seniors between the ages of 65 and 84 living in Maryland's Eastern Shore region, where fish and shellfish are eaten routinely. After their food intake was assessed, participants underwent eye exams. About 450 had AMD, including 68 who had an advanced stage of the disease, which can lead to severe vision impairment or blindness. In the United States, AMD is the major cause of blindness in whites, according to background information in the news release.

Prior evidence suggested that dietary zinc is similarly protective against AMD, so the researchers looked to see if zinc consumption from a diet of oysters and crabs reduced risk of AMD, but no such association was seen. However, the study authors theorized that the low dietary zinc levels relative to zinc supplements could account for the absence of such a link.

Anand Swaroop, chief of the neurobiology, neuro-degeneration, and repair laboratory at the U.S. National Eye Institute, interpreted the findings with caution. “It does make huge sense theoretically,” he said. “Photoreceptors have a very high concentration of a specific type of fatty acids and lipids, relative to many other cell types. So it would make sense that omega-3 consumption would be beneficial. The theory is sound.”

“However, I wouldn't want people to start taking grams of omega-3 to protect against AMD based on this finding because I'm not really sure that this study has sufficient power to draw any conclusions,” Swaroop added. “This is just a one-year analysis and AMD is a long-term disease. The correlation is important, and it should be explored further. But we need larger studies with longer term follow-up before being able to properly assess the impact.”

SOURCE: Anand Swaroop, Ph.D senior investigator and chief of neurobiology, neurodegneration, and repair laboratory, U.S. National Eye Institute, Bethesda, Md.; American Academy of Ophthalmology, news release, Dec. 1, 2010

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World’s Oldest Person Dies at 114

World’s Oldest Person Dies at 114
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Guinness World Records has reported the death of the world's oldest person aged 114 years and 357 days, a week shy of her 115th birthday.

Kama Chinen, a resident of a sub-tropical island in Okinawa, Japan, died on May 2, 2010. She lived to see three different centuries, the Gerontology Research Group (GRG) commented.
“Though confined to a wheelchair in her later years, Chinen enjoyed the wonders of nature and being outside,” the organization said.
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Okinawa has a reputation for its long-lived residents, put down to the local diet of green tea, miso soup, vegetables, rice and fresh fish.
The title of oldest human now passes to 114-year-old Frenchwoman Eugenie Blanchard, who was born in February 1896. She lives on the Caribbean island of Guadeloupe, GRG said.
Chiyono Hasegawa, 113, in southern Japan's Saga prefecture is now the country's oldest person.
Japan has the world's highest life expectancy, and Okinawa has been home to many centenarians, a fact variously attributed to the healthy diet and environment of the island.
According to the study, old Okinawans also have lower rates of cancer, in part due to a generally low caloric, low-fat and high-fiber diet that is rich in vegetables and fruits, as well as to their physical activity.
Average life expectancy in Japan climbed sharply after World War II. In 2008, life expectancy at birth was 86.05 years for women and 79.29 years for men, according to official statistics.

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Eating oily fish can protect women from infertility

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Eating a diet of plenty of oily fish daily can protect women against infertility, says a new study. Researchers have carried out the study of 70,000 nurses and found those who ate the most tuna, salmon, mackerel and other fish high in omega-3 fatty acids were nearly 22 per cent less likely to develop endometriosis which is known to causes infertility.

However, the study found that those whose diets were heavily laden with harmful transfats – chemically altered vegetable oils – found in thousands of products from cakes and biscuits to pies and chips were 48 per cent more at risk of developing endometriosis. The condition arises when cells normally found in the womb lining attach themselves to other parts of the pelvic area, causing inflammation and often leading to infertility.

The study, the largest to have investigated the link between diet and endometriosis, followed the nurses for 12 years from 1989. It found while the total amount of fat consumed did not matter, the type did.

Gynaecologist Dr Stacey Missmer, of Harvard Medical School, Boston, said her findings, not only suggest that diet may be important in the development of endometriosis but also provide more evidence for eliminating trans fats, which are used to bulk up foods and increase their shelf life.

“Millions of women worldwide suffer from endometriosis. Many have been searching for something they can do for themselves, or their daughters, to reduce the risk of developing the disease. These findings suggest dietary changes may be something they can do. The results need to be confirmed by further research, but this study gives us a strong indication that we are on the right track in identifying food rich in omega-3 oils as protective for endometriosis and trans fats as detrimental,” she said.

The study is published in the 'Human Reproduction' journal.

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