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Issue #38 (December 2017)

From the Editor

Volume 1

The flu season in the U.S. is starting to pick up. And it’s starting to look like this one’s going to be a doozy.

As of late November, the CDC has reported that 3 states in the gulf coast and southeast have high levels of flu activity, and overall activity is higher than it was at this time last year the U.S. This concords with the evidence from Australia, whose flu season ended recently since seasons there are opposite those in the U.S. There, the number of flu events, as well as hospitalizations and deaths related to flu infections, also ran high.

The predominant type of flu strain in the U.S. is also matching Australia’s experience. Both in Australia’s past flu season and the U.S.’s current one, H3N2 leads the pack as the major type of flu strain. This is bad news, since this strain tends to lead to more severe forms of illness, especially among children and people who are elderly.

The fact that H3N2 is predominating is also concerning because there’s reason to suspect this year’s flu shot may not protect very well against this strain. Data from the CDC showed that while the flu shot was on average 42% effective last flu season, the efficacy for H3N2 was only 32%. And in Australia’s past season, it’s looking like its efficacy for this particular strain was only around 10%. Part of the reason for the drop in efficacy may be due to the egg-based manufacturing process, which led to a mutation which makes this vaccine less effective.

While this seems like bad news all around, it shouldn’t keep anyone who’s able from getting their flu shot. After all, even a 10% chance of preventing H3N2 infection is better than none. In addition, protection against H1N1 and influenza B will probably be higher. And, importantly, getting the flu shot doesn’t just protect you, but also helps stop you transmitting the flu to those around you, including people who are especially vulnerable, like children, the elderly, and those who can’t get vaccinated.

Other ways to protect yourself and those around you include frequent handwashing, avoiding rubbing your eyes and nose, and covering your mouth with the crook of your elbow when you cough or sneeze. In this volume of the NERD, we also give you one more tool in time for the flu season: prebiotic and probiotic supplementation. Read on for more info!

Gregory Lopez, MA, PharmD
Editor-in-chief, Nutrition Examination Research Digest

Volume 2

Last month, the American College of Cardiology and the American Heart Association released new guidelines for the management of high blood pressure. Previously, hypertension was defined as having a pressure of 140/90. In the new guidelines, the bar for having high blood pressure drops to 130/80. Normal blood pressure is still defined as less than 120/80.

What made the headlines was that many more people would be diagnosed with hypertension. That’s certainly true. It’s also helpful, since the evidence strongly suggests that at the risk for cardiovascular problems is doubled at 130/80 compared to people with normal blood pressure. However, what wasn’t emphasized as much as I’d like was that this doesn’t necessarily mean that everyone who now has high blood pressure has to be put on drugs. Some certainly do, but the new guidelines have a lot to say about non-drug interventions as well.

Starting drug therapy straightaway is recommended for people with hypertension who have a blood pressure of 140/90 (now known as stage 2 hypertension), have cardiovascular disease, or are at a greater than 10% risk for it over the next 10 years. Otherwise, non-drug interventions are what’s recommended. And even for higher-risk individuals, lifestyle changes are recommended alongside drugs. So, either way, lifestyle plays a role.

The authors of the guidelines scoured the relevant recent literature to determine which non-drug interventions have the biggest proven impact on high blood pressure. They found that a DASH-like diet high in fruit, veggies, whole grains, and low in saturated and trans fats, had a big impact, lowering systolic blood pressure by over 10 mmHg on average. Weight loss, something we talk about quite a bit in the NERD, also had a big effect; the authors estimate that each kilogram in bodyweight lost will lead to a 1 mmHg reduction in blood pressure. Exercise can also play a role, with 120-150 minutes a week of moderate-intensity aerobic exercise leading to over a 5 mmHg drop in systolic pressure over time. Strength training works, too, but looks to be a little less effective than aerobic exercise. Limiting alcohol and salt intake can also help according to the guidelines, although there’s been some controversy in the literature recently about the latter.

While some supplements like garlic also have evidence for helping with high blood pressure, and drug treatment is needed for people at high risk, the fundamentals of diet and exercise play a huge role in helping manage high blood pressure as well as a healthy life in general.

Gregory Lopez, MA, PharmD
Editor-in-chief, Nutrition Examination Research Digest

See other articles in Issue #38 (December 2017) of Study Deep Dives.