Just Say NO to High Blood Pressure!

It has long been known that compounds known as nitrates have a beneficial effect for the cardiovascular system.  The most common example of this is nitroglycerin, a drug that is used for angina (chest pain due to spasm of blood vessels).  Nitrates are transformed by bacteria in the mouth to nitrites, which are then converted in the blood into nitric oxide (NO).  NO relaxes blood vessels, which can lower blood pressure.

In addition to pharmaceutical nitrates, attention has been focused recently on whole foods sources of nitrates.  Two studies took a look at the effects of beetroot juice on blood pressure.  In 2012, Australian researchers (1) found that consuming beetroot juice significantly lowered systolic blood pressure for up to 6 hours, compared to placebo.  Beets are a good source of nitrates, which the body can convert into NO.

But 500 g of beetroot juice is quite a bit.  Some clever Brits (2) therefore compared drinking liquid beetroot juice to consuming a special beetroot enriched bread.  They found that both were equally effective in lowering blood pressure, and the bread may be more palatable.  Furthermore, in their study, they noticed that the blood pressure lowering benefits persisted for 24 hours.

One caveat to keep in mind is that both of these studies were performed with healthy subjects.  However, eating more vegetables is definitely good for your health anyway, so increasing your beet intake is a good idea if you're trying to lower your blood pressure.  You can also look at other vegetables that are high in nitrates, such as radishes, carrots, and lettuce.  And don't forget the blood pressure lowering benefits of chocolate for dessert!

1.  Coles, L and Clifton, P.  Effect of beetroot juice on lowering blood pressure in free-living, disease-free adults: a randomized, placebo-controlled trial.  Nutr J. 2012; 11: 106.

2.  Hobbs DA, et al. Blood pressure-lowering effects of beetroot juice and novel beetroot-enriched bread products in normotensive male subjects. Br J Nutr. 2012 Dec 14;108(11): 2066-74. Epub 2012 Mar 14.

Red Meat and Heart Health: The Gut Bacteria Connection

There's been a lot of debate over the years as to whether or not red meat consumption increases our risk of developing heart disease. In the past, much of the research has focused on the high levels of saturated fat and red meat, and their impact on blood cholesterol levels. A new study just published this month in Nature Medicine suggests a new mechanism: the difference in the type of gut bacteria between meat eaters and non-meat eaters.  A nice summary of the study was discussed recently on the National Public Radio show, Science Friday.

The main focus of this new study is a compound called L-carnitine, which is found in abundance in red meat. The intestinal bacteria found in omnivorous humans (compared to vegetarians or vegans) are more likely to metabolize L-carnitine into a compound called trimethylamine-N-oxide (TMAO).  High levels of TMAO accelerate the process of atherosclerosis.

The findings of this study are consistent with the well-known pattern of the Mediterranean diet, which places a great emphasis on plant-based foods, and recommends red meat only once or twice per month (see the pyramid diagram below). The Mediterranean diet is the pattern of eating among people in Italy, Greece, and other Mediterranean regions, that has been associated with protection against chronic disease, and greater lifespan.  This study has generated considerable outrage and debate, especially among proponents of high-meat diets, such as the Paleo diet. However, there is much more research about the health benefits of a Mediterranean eating pattern.

Once again, we're just beginning to scratch the surface of the importance of the ecosystem living in our intestinal tract.  I recently reported that the normal flora living in our gut can have an influence on obesity and weight loss.  If the first hundred years of nutrition research has focused on identifying nutrient compounds, deficiency conditions, and toxicity, then the next hundred years could be looking more at the effects of normal flora on our health.

Intestinal microbiota metabolism of L-carnitine, a nutrient in red meat, promotes atherosclerosis.  

Nature Medicine

 

(2013)

 

doi:10.1038/nm.3145.  

Published online

 

07 April 2013

Coffee: Pain Reduction, Weight Loss, and More

For decades, it's been a given in natural health circles that coffee is a no-no. It's commonly one of the first things that people are asked to give up when going on a detox program, or any other recommendations for improving their health. Over the past decade or so, though, evidence has been mounting that there are actually many health benefits for that morning cup of joe.

One of the latest findings is that coffee may help to reduce pain.  In 2012, Norwegian researchers found that coffee drinkers reported about a 25% lower pain score than non-coffee drinkers in a simulated office work environment. This difference was true whether participants had chronic pain or not.

Other benefits that have been reported for coffee in recent years include:

• decreased risk of endometrial cancer, Parkinson's disease, Alzheimer's disease, and type 2 diabetes
• enhanced muscle growth
• assistance with weight loss (with green coffee bean extract)

The research on green coffee extract for weight loss was a small human trial, involving only 16 subjects. Doses used were in the range of 700 to 1000 mg per day.  However, the results were striking, and so far, and this supplement seems safe. It is inexpensive, and worth a try for a few months.

The main benefits of coffee seem to be related to its phytonutrient content-- those health promoting compounds found in plants that have antioxidant and other beneficial effects on the human body. These benefits seem to hold true whether the coffee contains caffeine or not. So if you're concerned about caffeine, due to its acute blood pressure raising effects, or its detrimental effects on sleep, you can drink decaf, and still enjoy the preventive medicine aspects of coffee.

One last thing to keep in mind: many of the health benefits of coffee can be counteracted if you add a lot of milk and sugar to it. The high saturated fat and empty calories would be more than enough to outweigh the phytonutrient effects.

For me, I'll be enjoying my cup of black half-caf in the morning all the more.