Cardiovascular health

A very large British study involving 1.1 million middle-aged women without prior vascular disease has found, over nine or so years, those who performed strenuous physical activity two to three times a week were about 20% less likely to develop heart disease, strokes or blood clots, compared to participants who reported little or no activity. However, those who reported doing strenuous activity daily had higher risk compared to those who only engaged in moderate amounts of activity.

http://www.eurekalert.org/pub_releases/2015-02/aha-waa021115.php

Armstrong, M. E. G., Green, J., Reeves, G. K., Beral, V., & Cairns, B. J. (2015). Frequent Physical Activity May Not Reduce Vascular Disease Risk as Much as Moderate Activity Large Prospective Study of Women in the United Kingdom. Circulation, 131(8), 721–729. http://doi.org/10.1161/CIRCULATIONAHA.114.010296

A small study involving 45 healthy, overweight or obese adults aged 21-70 has found that a diet including a daily Hass avocado was more effective than other cholesterol-reducing diets. Participants followed each of three diets for five weeks: one containing 24% fats and two containing 34% fats, one of which included an avocado and the other a comparable amount of high oleic acid oils (e.g. olive oil). There was a two-week break between each diet.

The avocado diet decreased bad cholesterol by 13.5 mg/dL, while LDL was decreased by 8.3 mg/dL on the moderate-fat diet and by 7.4 mg/dL on the low-fat diet.

http://www.eurekalert.org/pub_releases/2015-01/ps-aaa010715.php

Wang, L., Bordi, P. L., Fleming, J. A., Hill, A. M., & Kris Etherton, P. M. (2015). Effect of a Moderate Fat Diet With and Without Avocados on Lipoprotein Particle Number, Size and Subclasses in Overweight and Obese Adults: A Randomized, Controlled Trial. Journal of the American Heart Association, 4(1), e001355. http://doi.org/10.1161/JAHA.114.001355

A small study involving 15 adults with moderate-to-severe obstructive sleep apnea and 19 controls with mild or no sleep apnea has found that predicted peak oxygen uptake (VO2), a measure of aerobic physical fitness, was significantly lower in those people with moderate to severe obstructive sleep apnea. Moreover, the number of times a person stopped breathing, for 10-seconds or more, per hour of sleep, predicted 16% of the variability observed in the group's peak VO2.

People who suffer from apnea are more likely to be obese and thus would be expected to be less fit as well, but even compared to people with similar BMI, the apnea patients had a reduced aerobic fitness. It's suggested that the sleep apnea itself causes structural changes in muscle that contributes to exercise problems.

VO2 max measurements may be an early marker for those who are at higher risk of stroke and heart attack

http://www.eurekalert.org/pub_releases/2014-12/aaos-sls120114.php

http://www.eurekalert.org/pub_releases/2014-11/uoc--sal112414.php

Beitler JR, Awad KM, Bakker JP, Edwards BA, DeYoung P, Djonlagic I, Forman DE, Quan SF, Malhotra A. Obstructive sleep apnea is associated with impaired exercise capacity: a cross-sectional study. J Clin Sleep Med 2014;10(11):1199-1204.

Anecdotal and scientific evidence suggests curcumin, a compound found in turmeric, promotes health because it lowers inflammation. However, it is not absorbed well by the body. Most curcumin in food or supplements stays in the gastrointestinal tract, and any portion that's absorbed is metabolized quickly.

A new study thinks they've come up with a better and more effective way to deliver curcumin, and in so doing has demonstrated how it works. Curcumin powder was mixed with castor oil and polyethylene glycol, allowing it to dissolve and be more easily absorbed by the gut to enter the bloodstream and tissues.

When this was given to mice who had been injected with an extract that stimulates an immune reaction, a key protein that triggers an immune response was blocked. The mice given plain curcumin, on the other hand, showed the same protein actively triggering an immune response.

The emulsified curcumin also stopped recruitment of macrophages. Inflammation triggered by overactive macrophages has been linked to cardiovascular disease, disorders that accompany obesity, Crohn's disease, rheumatoid arthritis, inflammatory bowel disease, diabetes and lupus-related nephritis.

http://www.eurekalert.org/pub_releases/2014-11/osu-nra110614.php

A small study involving 11 non-obese, healthy men aged 20-35, has found that blood flow in leg arteries is significantly impaired after three hours of sitting, but not if they walk for five minutes every hour.

When people sit, slack muscles do not contract to effectively pump blood to the heart. Blood can pool in the legs and affect the endothelial function of arteries, or the ability of blood vessels to expand from increased blood flow. Impaired endothelial function is an early marker of cardiovascular disease.

In the study, participants sat for three hours without moving their legs, while the functionality of the femoral artery was taken at baseline and every hour. This showed that the expansion of the femoral artery as a result of increased blood flow was impaired by as much as 50% after just one hour.

In another session, they again sat for three hours, but also walked on a treadmill for 5 minutes at a speed of 2 mph at the 30-minute mark, 1.5-hour mark and 2.5-hour mark. In this case, arterial function stayed the same throughout the session.

http://www.eurekalert.org/pub_releases/2014-09/iu-tsw090514.php

Thosar, S. S., Bielko, S. L., Mather, K. J., Johnston, J. D., & Wallace, J. P. (2015). Effect of Prolonged Sitting and Breaks in Sitting Time on Endothelial Function: Medicine & Science in Sports & Exercise, 47(4), 843–849. http://doi.org/10.1249/MSS.0000000000000479

A Czech study involving 146 people with mild to moderate risk of cardiovascular disease has found that moderate wine drinking was only protective in people who exercised.

Participants were randomly assigned to one year of moderate consumption of red wine (Pinot Noir) or white wine (Chardonnay-Pinot) from the same year and wine region of the Czech Republic. They had to keep a logbook on their consumption of wine and other alcoholic beverages, medication use, and amount and type of exercise. They were required to return the corks from the wine bottles to confirm that they had drank the wine rather than sold it.

The study was looking for a rise in HDL cholesterol, indicating a protective effect against cardiovascular disease. However, there was no change in HDL cholesterol levels by the end of the study in either the red or white wine groups. Nor did it appreciably affect blood glucose, triglycerides, or levels of inflammatory markers like C-reactive protein, although LDL cholesterol was lower in both groups while total cholesterol was lower only in the red wine group.

However, those participants who engaged in regular exercise at least twice a week did show an increase in HDL cholesterol, as well as a decrease in LDL and total cholesterol. This occurred in both red and white wine groups.

Of course, the study didn't include a control group of people engaging in regular exercise who didn't drink, so all we can really say (and it's certainly worth saying) is that moderate wine drinking doesn't seem to help protect against cardiovascular disease, and that despite all the hype around red wine, with its greater antioxidants and resveratol, there's no evidence it's any healthier than white wine.

http://www.eurekalert.org/pub_releases/2014-08/esoc-wop082614.php

http://www.theatlantic.com/health/archive/2014/09/working-with-the-wine-not-against-it/379504/

Taborsky M, Ostadal P, Petrek M. A pilot randomized trial comparing long-term effects of red and white wines on biomarkers of atherosclerosis (in vino veritas: IVV trial). Bratisl Lek Listy. 2012;113(3):156-158.

Telomeres are the protective caps at the ends of chromosomes that affect how quickly cells age. With age, they shorten, and as their structural integrity weakens, the cells age and die quicker. Telomere length thus is a biomarker of cellular age. Stress is also thought to shorten telomere length.

A year-long study that looked at the effects of three healthy behaviors in 239 post-menopausal, non-smoking women has found that women who engaged in lower levels of healthy behaviors showed a significantly greater telomere shortening for every major life stressor that occurred. However, stress didn't lead to greater shortening in those women who maintained active lifestyles, healthy diets, and good quality sleep.

Shorter telomeres have become associated with a broad range of aging-related diseases, including stroke, vascular dementia, cardiovascular disease, obesity, osteoporosis diabetes, and many forms of cancer.

http://www.eurekalert.org/pub_releases/2014-07/uoc--hlm072414.php

Puterman, E., Lin, J., Krauss, J., Blackburn, E. H., & Epel, E. S. (2015). Determinants of telomere attrition over 1 year in healthy older women: stress and health behaviors matter. Molecular Psychiatry, 20(4), 529–535. http://doi.org/10.1038/mp.2014.70

A study looking at the workout habits of more than 55,000 individuals for 15 years has concluded that running can reduce a person’s all-cause mortality rate by 30% and cardiovascular mortality rate by 45%. This equated to a difference of about three years of life.

But the really exciting news is that people who ran less than an hour each week showed the same mortality benefits compared to those who ran more than three hours in each week. Note that this is more about running, say, ten minutes every day, than only running once a week for a longer time! You don't have to run fast, either. Those running more slowly (< 6 miles/hour) got the same benefits.

Not running had about the same negative effect on life expectancy as having hypertension.

Around 24% of the participants did some running. The average age was 44.

http://www.futurity.org/even-short-slow-running-can-extend-lifespan/

Lee D, Pate RR, Lavie CJ, Sui X, Church TS, Blair SN. Leisure-Time Running Reduces All-Cause and Cardiovascular Mortality Risk. J Am Coll Cardiol. 2014;64(5):472-481. doi:10.1016/j.jacc.2014.04.058.

A Canadian study involving 141 people with Type 2 diabetes, who ate either a low glycemic index diet that included bread made with canola oil, or a whole wheat diet known to reduce the risk of cardiovascular disease, found that those on the canola bread diet experienced both a reduction in blood glucose levels and a significant reduction in LDL, or "bad," cholesterol. Moreover, the canola bread diet seemed to have the most significant impact on people who needed help the most — those whose HbA1c test measuring blood glucose over the previous two or three months was highest.

On the other hand, those on the whole wheat diet seemed to have better blood flow after 12 weeks than those on the canola bread diet.

http://www.eurekalert.org/pub_releases/2014-06/smh-rsb061314.php

Jenkins, D. J. A., Kendall, C. W. C., Vuksan, V., Faulkner, D., Augustin, L. S. A., Mitchell, S., … Leiter, L. A. (2014). Effect of Lowering the Glycemic Load With Canola Oil on Glycemic Control and Cardiovascular Risk Factors: A Randomized Controlled Trial. Diabetes Care, 37(7), 1806–1814. http://doi.org/10.2337/dc13-2990