Monday, December 13, 2010

Wholegrains reduce stroke by as much as drugs (?)

This small study is interesting but does not really encourage direct replication. The most marked change in symptoms that they observed was a 6 mmHg drop in systolic blood pressure. A drop as small as that would certainly have no effect on mortality at all in most cases. By way of comparision, systolic blood pressure categories normally move upwards in steps of 20 mmHg. If the finding had emerged from a study of high-risk individuals, it would have been more impressive. But it did not. It concerned normals. Generalizing results obtained with normals to high-risk individuals may not work at all

Eating more whole-grain bread, rice and oats could be as effective at drugs at reducing the risk of stroke, research by Aberdeen University has found.

Researchers asked 200 people to eat a diet with three portions of whole grains per day or none. A diet high in fibre is known to reduce blood cholesterol and improve digestive health. It was found that the diet rich in wholegrains reduced blood pressure.

Dr Frank Thies, Senior Lecturer at The Rowett Institute of Nutrition and Health University of Aberdeen, who led the study, said: "We observed a decrease in systolic blood pressure in the volunteers who ate the whole-grain foods, and this effect is similar to that you might expect to get from using blood pressure-lowering drugs.

“This drop in systolic blood pressure could potentially decrease the incidence of heart attack and stroke disease by at least 15 and 25 per cent respectively."

A portion is counted as around 13 to 16g of whole grains, the equivalent of around half a cup of oats or brown rice or a slice of whole-grain bread.

The findings were published in the American Journal of Clinical Nutrition.

Effect of increased consumption of whole-grain foods on blood pressure and other cardiovascular risk markers in healthy middle-aged persons: a randomized controlled trial

By Paula Tighe et al.


Background: Three daily portions of whole-grain foods could lower cardiovascular disease risk, but a comprehensive intervention trial was needed to confirm this recommendation.

Objectives: We aimed to assess the effects of consumption of 3 daily portions of whole-grain foods (provided as only wheat or a mixture of wheat and oats) on markers of cardiovascular disease risk in relatively high-risk individuals.

Design: This was a randomized controlled dietary trial in middle-aged healthy individuals. After a 4-wk run-in period with a refined diet, we randomly allocated volunteers to a control (refined diet), wheat, or wheat + oats group for 12 wk. The primary outcome was a reduction of cardiovascular disease risk factors by dietary intervention with whole grains, which included lipid and inflammatory marker concentrations, insulin sensitivity, and blood pressure.

Results: We recruited a total of 233 volunteers; 24 volunteers withdrew, and 3 volunteers were excluded. Systolic blood pressure and pulse pressure were significantly reduced by 6 and 3 mm Hg, respectively, in the whole-grain foods groups compared with the control group. Systemic markers of cardiovascular disease risk remained unchanged apart from cholesterol concentrations, which decreased slightly but significantly in the refined group.

Conclusions: Daily consumption of 3 portions of whole-grain foods can significantly reduce cardiovascular disease risk in middle-aged people mainly through blood pressure–lowering mechanisms. The observed decrease in systolic blood pressure could decrease the incidence of coronary artery disease and stroke by ≥15% and 25%, respectively.


Vitamin D and plenty of sun give a ray of hope in the breast cancer fight

This is rather a wacky set of results. It tells you that pill popping won't help you unless you live in the sunnier parts of France. Since the sunnier parts of France are more desirable we may therefore simply be seeing that richer and healthier people move there. There is a considerable association between wealth and health

An unmentioned implication of the finding is that, given the overall lack of association between pills and health, the benefit in sunnier areas must indicate that pill popping is BAD for you in the gloomier part of France. All rather absurd

A diet packed with Vitamin D combined with high levels of sunlight could reduce the risk of breast cancer in women by 43 per cent.

A new study of 70,000 women conducted over ten years revealed that a diet high in Vitamin D had no effect on its own. One theory is that consuming a diet rich in Vitamin D makes a difference only when there is already a sufficient amount produced from sun exposure. Therefore, when sun exposure is low, diet intake does not make any difference to risk of disease.

However, the study concludes that an increase in overall Vitamin D intake should be encouraged, including fortifying foods with it - a practice already under way in America.

Laboratory studies have suggested that Vitamin D may have a number of anti-cancer effects and has been shown to slow the spread of cancer cells.

Researchers at the Centre for Research in Epidemiology and Population Health in France tracked 67,721 women aged 41 to 72 for a decade to see who developed breast cancer. Their diets and ultraviolet levels where they lived were then analysed to calculate the risks. At the end of the ten-year period 2,871 breast cancers had been diagnosed.

Some 45 per cent of their dietary Vitamin D came from fish and seafood, 16 per cent from eggs, 11 per cent from dairy products, ten per cent from oils and margarine, and six per cent from cakes.

Living in regions with the highest ultraviolet levels was associated with a significant - nearly ten per cent - reduced risk compared to those women in the areas with the lowest UV.

But the biggest effects were seen when the researchers examined the impact of both sources of the vitamin. In regions which had the highest level of daily ultraviolet, the women with higher level of Vitamin D in their diets or who took supplements had a breast cancer risk 32 to 43 per cent lower compared with those with the lowest vitamin intake. 'Our findings support a protective effect of sun exposure on the risk of breast cancer,' says Dr Pierre Engel, who led the study.

'It is difficult to have a simple public-health message without thinking about the risk of skin cancer. We must be very cautious but we think that increased Vitamin D levels by reasonable sun exposure and higher dietary intakes should be encouraged.

'As suggested by our results, diet alone seems unable to provide an adequate amount of Vitamin D.'

High dietary and supplemental Vitamin D intakes are associated with a reduced risk in women living in areas with higher UV exposure. When a sufficient Vitamin D level is secured through UV exposure, variations in dietary intake may become of importance. When the underlying level of Vitamin D photosynthesis is low, variations in dietary intake are insufficient to make any difference in disease risk.

'These results confirm other work we have carried out showing that women with high blood Vitamin D levels are at reduced risk of breast cancer compared to those who have very low levels,' adds Dr Engel.


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