While I am of the mind that quality of carbs is just as important, if not more so, than quantity of carbs, I do recognize the fact that low-carb diets work well for a lot of people, and can be especially beneficial as a dietary intervention in people with certain conditions (like diabetes and epilepsy).
A low-carber's dream
Unfortunately people like the American Dietetic Association (of which I am a part of) and a lot of MDs have warned us of the “dangers” of a low-carb, high-fat, high-protein diet. You know like potential kidney damage, increased cardiovascular disease risk from that extra dietary fat, and other non-sense that has just not been found to be true yet is somehow taught in nutrition undergrad courses and written about incessantly.
Maybe these RDs are just afraid that their constant recommendations of high-carb low-fat diets will be shown to be no more beneficial or safe than other methods?
Thankfully actual research is being done on the topic, and it is showing that low-carb diets are actually not dangerous. Shocking, I know.
Recently a two year study was conducted comparing a low-carb Atkins style diet to an ADA recommended low-fat low-calorie diet. The researchers measured weight loss, HDL (the “good” cholesterol) and other markers of health in 307 adults.
At the end of two years both groups lost the same amount of weight on average – about 15lbs. The biggest difference between the two groups was actually in cardiovascular disease risk.
If you had asked a traditional MD or RD which group would decrease its cardiovascular disease risk the most after this trial, they undoubtedly would have answered with the low-fat group. Obviously, its low-fat, and fat contributes to heart disease right?
Surprisingly, this study found that the low-carb dieters increased their HDL by 23%, which is comparable to the boost from a lot of pharmaceuticals. Both groups had equal improvements in LDL, which I am sure would surprise a lot of traditionalists as well, since the low-carb group most definitely are more fat and more saturated fat, and saturated fat raises LDL and therefore heart disease risk right? Hhmmm…
There was an initial rise in LDL in the low-carb group, but by the two year mark this had dropped and their LDL levels were equal to the low-fat group. This is expected as the body adjusts to the increase in saturated fat and cholesterol in the diet, and this has been discussed ad nauseum over at wholehealthsource.
The moral of the story is that if you choose to eat a low carb diet for whatever reason, as long as you choose real whole foods you will markedly improve your health and not increase your cardiovascular disease risk.
I came across some really interesting new research that I thought I would share with you guys.
There was a recent study looking at the effects of green and black tea, as well as rooibos tea on angiotensin-converting enzyme (ACE). I have written about tea many times, check here and here for more.
On a quick aside, my favorite rooibos tea (above) was ranked as the best rooibos tea on realsimple.com. Check out their list of best teas.
Angiotensin-converting enzyme has two main functions: converting angiotensin I to angiotensin II and to degrade bradykinin. This is a problem because angiotensin II constricts blood vessels and bradykinin relaxes blood vessels.
As such ACE inhibition is a goal in the treatment of many conditions: high blood pressure, heart failure, diabetic nephropathy, and type 2 diabetes.
The problem is there are many problems associated with ACE inhibitors: hypotension, cough, hyperkalemia, fatigue, and renal impairment. Renal impairment is a problem with all ACE inhibitors, with no known cause. This can be especially problematic when taken in conjunction with NSAIDs and a diuretic there is a very high possibility of going into renal failure.
As such it is important to know which real whole foods can impart some of the benefits of ACE inhibitors, without the side effects (this is true of all drugs really).
This study had patients drink 400ml of green, black or rooibos tea once daily. It then monitored ACE activity for up to 3 hours after consumption.
It was found that green tea and especially rooibos tea significantly inhibited ACE activity. While this does not definitely show that consumption of green and rooibos tea can be used to replace ACE inhibitors, it does show that they might help in the treatment of high blood pressure and can be used as part of a dietary intervention before putting someone on powerful ACE inhibitors.
More research is needed to see how much this ACE inhibition actually contributes long-term benefits, but the results are promising none the less.
Here is the study abstract if you want to take a look at it yourself.
A former client sent me an interesting article about exercise. We have known for a long time now that exercise is the closest thing we have to a fountain of youth.
Exercise improves quality of life in innumerable ways. It improves cognitive function, cardiovascular health, improves blood vessel function, improves mood and decreases risks for a plethora of diseases.
Even knowing all that, we still have never really known why exercise works. What is it that it actually does to drastically improve our health?
This article on boston.com delves into some new research on that very topic. It is just scratching the surface, but already revealing some interesting facts about the benefits of exercise.
These researchers have looked at exercise and found that there are 21 metabolites in the blood stream that respond to exercise. They also found that fit people respond to exercise differently than unfit people.
Of these 21 molecules some of they indicate how carbohydrates, sugar and fat are oxidized as fuel, while others are involved in controlling insulin levels and cellular stress. Clearly this makes tremendous sense, since we know that exercising will improve glucose tolerance, insulin sensitivity, decrease fasting glucose and insulin and is associated with longer life expectancies.
The scientists took blood from people before and after the 2006 Boston Marathon, as well before, during and after subjects rode exercise bikes or ran on treadmills.
They measured the changes in 200 metabolites, and by finding which ones responded to exercise they pulled back the curtain a little bit on why exercise is so good for us.
They found that fit people and unfit people had different responses. Fit people had levels of glycerol twice as high as unfit people as well as higher levels of niacinamide. Glycerol is the backbone of fatty acids, and is released into the blood stream when these fatty acids are oxidized as fuel. Niacinamide is involved in regulating insulin levels.
There are many more questions to be answered, but “The studies to date are really what we like to think of [as] the first comprehensive chemical snapshot of exercise,’’ said Dr. Robert Gerszten, senior author of the paper and director of clinical and translational research for the MGH Heart Center.
Posted on August 5th, 2010 by Brian St. Pierre
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