Category: Longevity & Health

Research from Brigham And Women’s Hospital in Boston, USA, suggests that servings of two or more fish per week are associated with a lower risk of hearing loss in women. Data on over 65 000 women followed over the period 1991 to 2009, showed that compared to women who rarely consumed fish, those women who had two or more servings per week, were 20% less likely to experience hearing loss. Higher intake of long-chain omega-3 polyunsaturated fatty acids (PUFA) showed a similar association.

Dr Sharon Curhan, who led the study, said,“Although a decline in hearing is often considered an inevitable aspect of aging, the identification of several potentially modifiable risk factors has provided new insight into possibilities for prevention or delay of acquired hearing loss. Consumption of any type of fish (tuna, dark fish, light fish, or shellfish) tended to be associated with lower risk. These findings suggest that diet may be important in the prevention of acquired hearing loss.”

(Fish and fatty acid consumption and the risk of hearing loss in women. American Journal of Clinical Nutrition. Online 10 September 2014.)

Research from the University of Warwick has found that higher fruit and vegetable consumption is associated with better mental wellbeing. In a survey of 13 983 adults in England, looking at factors such as health, obesity, smoking and alcohol consumption, 33% of participants with high mental wellbeing, were found to be eating five or more portions of fruit and vegetables daily. Across the study as a whole, high fruit and vegetable consumption was associated with both high likelihood of good mental wellbeing and reduced likelihood of poor mental wellbeing.

The researchers believe that their findings add to the mounting evidence that fruit and vegetable intake could be a way of enhancing mental wellbeing whilst at the same time preventing heart disease and cancer.

(Major health-related behaviours and mental well-being in the general population: the Health Survey for England. BMJ Open, 19 September 2014. http://bmjopen.bmj.com/content/4/9/e005878.full)

Researchers at the London School of Hygiene and Tropical Medicine have found that commuters who travel to work by walking, cycling or public transport, have a significantly lower body mass index (BMI) and percentage body fat, compared with those who use private transport (predominantly the car, but also taxi, moped and motorbike).

A total of 15 777 people were included in the study. Factors such as age, disability, diet quality, participation in sport, and physical activity in the workplace, were all allowed for in anticipation that they might affect any association between commuting mode and obesity. Men who commuted via public or active transport modes were found to have BMI scores respectively 1.10 and 0.97 lower than those using private transport. For women, the corresponding figures were 0.7 and 0.87.

A key finding was that the effects observed for public transport were very similar in size to those for walking or cycling, probably due to walking between transport hubs and making journey connections. The observed effect size for men of around 1 BMI point suggests that, for the average man in the sample (43 years old, 176 cm tall, weight 86 kg, and BMI 27.8), this would equate to a difference in weight of 3 kg (almost half a stone). For the average woman in the sample (43 years old, 163 cm tall, weight 72.8 kg, BMI 27.4), an effect size of around 0.7 BMI points would correspond to a difference in weight of approximately 2.5 kg (5.5 lb).

(Associations between active commuting, body fat, and body mass index: population based, cross sectional study in the United Kingdom. British Medical Journal, online 19 August 2014.)

An international team of researchers, led by Dr David Llewellyn at the University of Exeter Medical School, has found that vitamin D deficiency is associated with a substantially increased risk of dementia and Alzheimer’s disease in older people. The team followed 1658 individuals in the US, who were initially free from dementia, cardiovascular disease and stroke, for a mean of 5.6 years. Their blood vitamin D levels were monitored and classified as severely deficient, moderately deficient or sufficient.

The researchers found that those participants who were moderately deficient in vitamin D had a 53% increased risk of developing dementia of any kind, and this risk increased to 125% in those who were severely deficient. Similarly, for Alzheimer’s disease, the moderately deficient group were 69% more likely to develop this type of dementia, and this risk increased to 122% for participants who were severely deficient.

Dr Llewellyn commented that the association was twice as strong as anticipated, and that clinical trials are now needed to establish whether eating foods such as oily fish or taking vitamin D supplements can delay or even prevent the onset of Alzheimer’s disease and dementia. The team outlines how their study design makes reverse causation unlikely (dementia itself leading to lower vitamin D levels), and that their findings support the idea that vitamin D may possess a neuroprotective effect.

(Vitamin D and the risk of dementia and Alzheimer disease. Neurology Journal, on-line 6 August 2014. Link Between Dementia and Vitamin D Confirmed

A large study undertaken at Harvard Medical School seems to show that people who include significant quantities of nuts in their diets, can reduce their mortality risk: those who ate nuts seven or more times per week, reduced their risk of dying by around 20%. The researchers followed 76000 women and 42000 men for between 24 and 30 years, during which time the subjects kept records of their consumption of nuts. On analysis, both nuts and peanuts were found to reduce the chance of dying from cardiovascular disease, cancer, diabetes, infectious diseases, lung and kidney diseases.

Parallels have been found in other research from Iowa, the UK and Holland. The researchers speculate that nutrients in nuts, such as unsaturated fatty acids, high-quality protein, fibre, vitamins (folate, niacin, vitamin E), minerals (potassium, calcium, and magnesium), and plant chemicals (carotenoids, flavonoids, and phytosterols), may confer cardioprotective, anti-cancer, anti-inflammatory, and antioxidant properties.

(Association of nut consumption with total and cause-specific mortality. New England Journal of Medicine, 21 November 2013.)

Meanwhile, research at Loma Linda University in California, suggests that walnuts may have the ability to prevent “bad” cholesterol (LDL) from oxidising and damaging our blood vessels. The researchers wanted to build on previous work which has shown associations between high nut consumption and lower rates of cardiovascular disease and obesity. Although this is normally attributed to the presence in nuts of unsaturated fatty acids, they were interested in whether other constituents are preventing oxidative damage to the body. Sixteen healthy volunteers were given a breakfast of either 90g walnuts with water, or a breakfast similar in macronutrients made from olive oil, white bread, dried egg powder and water. Blood analysis would appear to indicate an antioxidant effect aswell as reduced inflammatory responses in individuals when consuming the walnut meal.

(Effect of a walnut meal on postprandial oxidative stress and antioxidants in healthy individuals. Nutrition Journal, Volume 13, 2014.)