July 4, 2007

Chocolate and BP--Another Stupid Study!

If you have diabetes, controlling your blood pressure is the next most important thing you can do to keep yourself healthy after controlling your blood sugar.

So you probably were thrilled this morning when you saw some version of this headline in today's paper: "Dark Chocolate lowers blood pressure!" But before you hit the Hershey's, it's worth taking a look at those pesky details.

Here are two different online versions of the story you can refer to, each includes only part of the data released to the press:

Dark chocolate in a medicinal light

Dark Chocolate Lowers Blood Pressure, New Study

In the words of the first article: The study took "44 adults ages 56 to 73 who had untreated pre-hypertension or mild, stage 1 hypertension. Test participants were divided into two groups. One consumed a daily dose of dark chocolate; the other the same amount of white chocolate."

The second version includes an important fact ommitted in the first: "Every day for 18 weeks, the volunteers were instructed to eat one-square portions of a 16-square Ritter Sport bar, or a similar portion of white chocolate. White chocolate doesn't contain cocoa."

So, after consuming their square of Ritter Sport dark chocolate every day "Systolic blood pressure, the top number, fell an average of nearly three points and diastolic dropped almost two points in the group that ate dark chocolate, compared with no change in blood pressure readings in the group eating white chocolate."

Sounds pretty good doesn't it?

But here's the kicker. In over half the versions of the story which I read online the following piece of information was omitted:
Average blood pressure at the start of the 18-week test was 147 over 86.

This means that at the end of the study the average blood pressure was 144 over 82, which I'm sure your doctor will confirm is much too high!

So here's what the journalists should have been asking, but didn't ask.

1. Why were people with damagingly high blood pressures allowed to maintain those damagingly high blood pressures for 18 weeks without being put on one of the many effective drugs that could have lowered them rather than being subjected to what turned out to be a feeble and mostly ineffective treatment?

2. Why didn't anyone ask whether German candy manufacturer, Ritter Sport, whose candy was used exclusively in this study funded this German study? If they did, why didn't someone point out the ethical issues involved in delaying treatment for high blood pressure for 18 weeks in order to promote the dubious health benefits of their candy?

I like chocolate as much as the next woman, possibly more. So, trust me, if dark chocolate had healing properties, I'd be healed!

But this study, contrary to the headline, really shows that eating chocolate, whatever its benefits, does not provide enough improvement in blood pressure to make chocolate an alternative to one of the more effective methods available for getting blood pressure control. And when the chocolate companies are rolling out $3 chocolate bars plastered with health claims, this is worth keeping in mind.

Here are a couple of tried and true methods for controlling your blood pressure that you should be aware of:

1. Cut your carbs. A large proportion of those who adopt a lower carbohydrate diet sees their blood pressure drop.

2. Cut your salt intake. Many people are salt sensitive, and if you are one, cutting down on salt can make a huge difference. Try to keep your daily intake under 1 gram. Hint: one half can of canned soup has an entire day's worth of salt in it. You don't even want to know about what's in "snack" food.

3. Exercise regularly.

4. Lose weight if you are able.

3. If you are still running a blood pressure higher than normal (which tops out at 120/80) talk to your doctor about starting what would be the appropriate blood pressure medication for you. If you have diabetes, it should NOT be a diuretic (hydrocholorothiazide) as these drugs raise blood sugars. Lisinopril or another ACE inhibitor is the recommended drug. A month's worth of Lisinopril can be bought for $4 at Wal-Mart so cost shouldn't be a problem. If you can't take an ACE inhibitor, an ARB is recommended. Both these classes of drugs fight insulin resistance and also protect the kidneys.


Anonymous said...

"Cut your carbs. A large proportion of those who adopt a lower carbohydrate diet sees their blood pressure drop. "

Good lord, you are so full of it. There is no evidence of this at all.

Jenny said...

If you put your energy into reading the research rather than posting anonymous snarls, you'd have seen the publication in JAMA of a Stanford study just this March which found that people on the Atkins diet not only lost more weight than those on three other popular diets, they improved their blood pressure and cholesterol.

Here's a release the details the findings;

Here's the abstract from JAMA

Anonymous said...

If you put your energy into actually reading all the research a topic rather than cherry picking out something that seems to support your viewpoint (LOW CARB is GREAT. LOW CARB IS THE SOLUTION TO EVERYTHING. LOW CARB WILL CURE CANCER. LOW CARB WILL BRING WORLD PEACE) and ignoring anything that shows otherwise, then you might get somewhere.

Its not that I'm opposed to low carb, I'm opposed to nonsense which makes bogus claims about low carbs or any diet. Or any drug for that matter. In your view, all drugs are evil, because they can't get your A1c below 5% (and whats your a1c on insulin and low carb ? below 5% ? )

Here's another JAMA study

This says clearly that there were no "..no significant effects on blood pressure .. at 1 year" from any diet (including the Atkins low carb diet).

Is that the end ? No. Some people do respond very well to a low carb diet and do reduce their weight a fair amount, which probably helps BP. But a lot of people (in fact 90-95%) have essential hypertension with no clear cause.

But I forget. You KNOW the cause. You KNOW the cure. Its LOW CARB !! LOW CARB CURES EVERYTHING

Jenny said...

Nowhere in these postings will a rational person see me saying that Low Carb is the only way to control blood sugar or that it works for everyone.

I DO suggest that cutting carbs is a great place to start, because it DOES work for a lot of Type 2s. And surprising numbers of people with Type 2 diabetes have NEVER been instructed that cutting carbs will greatly improve their blood sugars. So it is well worth informing them.

Nowhere do I write that any drug is "evil" because it can't achieve an under 5% A1c. I do consider oral drugs problematical if people taking them can't achieve the 6.5% A1c goal that endocrinologists currently recommend, particularly if doctors don't get more aggressive to lower blood sugars drugs when A1cs are higher than 6.5%.

I don't know what alternative universe you inhabit, but most of the Type 2s I run into are running A1cs well over 7%--often over 8% and their doctors are not urging them to get more aggressive. It is news to some of them that a 7.5% A1c represents damagingly high blood sugar, as it does.

My A1c on insulin is 5.5%, with a moderate carb intake around 110 grams a day. My waking blood sugar is around 92 and it's in the 80s before meals. My post-meal numbers almost never go over 140 mg/dl and they rarely over 120 mg/dl. Those are my targets and I'm happy with them.

If you search on Google Groups you'll find many people reporting that their blood pressure dropped fairly quickly after they started a low carb diet, often before they had lost significant amounts of weight. For the record, mine did not, but so many other people did experience this effect, I thought it worth mentioning.

And if you'd paid attention to the article you'd see that I mentioned a number of other different treatment approaches that are worth trying if cutting carbs doesn't do the job.

But given the problems people have with medication, a drug-free approach that works a lot of the time is well worth metioning.

Anonymous said...

Sigh. Jenny, why is it that the snarly commenters are always Anonymous?

Keep up the good work. I was on vacation and missed reading your insights. I haven't done a thing to catch up with all the household stuff that accumulates while gone, but I'm having a great time catching up on your blog posts.


Anonymous said...

Ok, i will start my comment about what is hypertension.
The North-American people says that any blood pressure (BP) higher than 120/80 is high and deserves some medication. In many counrtys around the world that isnt true, in some you need to be more than 140/90 to receive some drugs, less this is only exercise, lose weight and diet. We have the normal pressure (low 120/80), pre-hypertension, Stage 1,2,3 (all above 140/90) SO it isnt "much too high" as you said, is high, but you can handle easy with that. And 147/86 is stage 1, so can be much higher, and almost a lot of people discovered their problem more than this.
Comment: about use medication in BP lower than 140/90, lot of doctors around the world says that is some researchs created by pharmaceuticals industries to sell more drugs. (remeber your second question???)

Second important note about hypertension (and linking with this blog), diabetes. The most important damage are chronic, so if you be for a long time without control, that will make your health be poor. Why i said that? Because when you said "Why were people with damagingly high blood pressures allowed to maintain those damagingly high blood pressures for 18 weeks". Thats One of my aswers to your question. Making a people with stage 1 and pre-hypertension for 18 weeks for a trial will not make important damages, and specially when your are trying to test a new thing. How do you think they does the test with some new drugs. It is the same way, they leave the people without the good known drug to test the new uncertain for a period of time. If in this period the study goes okay, they maitain, if start to go wrong they stop. If you go and study how to make a reasearch you will see, that is basic. Thats why the journalists dont ask that. And more interesting, any research released in a important medical journal (as this one that been realeased in JAMA), need a ethical commision and they will care with all ethical problems.

The second question, a good one.
"2. Why didn't anyone ask whether German candy manufacturer, Ritter Sport, whose candy was used exclusively in this study funded this German study? If they did, why didn't someone point out the ethical issues involved in delaying treatment for high blood pressure for 18 weeks in order to promote the dubious health benefits of their candy?"
You have a nice point to ask about Ritter and Germany, yeah isnt good to say that ritter has been used, Or even any drugs, and often the commercial name is hiden from the article to be published, so I don´t believe that is true that the original article has been publishing saying that otherwise will not be realeased on JAMA. Maybe someon has make a new version from the article or have get some secret informations. But if we start to comment that, about industry and influence in research, we will be hours here and will not finish our talk.
But to real answer your question lets make another question.
"Why didn't anyone ask this when some industry make test with combined anti-hypertesions drugs (that they sells), when they know that some other combination is definitely much better and efficienty?" Just look Lancet this week, they published a study with combination of Renin Inhibitor and ARB (2 commons drugs for hypertension but isnt nice to use combined, but a industry sell it), and says that the combination is good, but the usual combination is also good, so why test??? To study what??? Study if they can sell their products??? And more interesting they used the same way to study. We have a lot of this been done and is common, it is right? I dont think so. But open your mind to see more of this and you will see that is all around.

Summarizing and answering you 2 question, as it was to similar. To know if someone new works you need to test and compare, so if you want to see if a drug is good, a combination of drug is good, or even if a diet is good, you need to test. And to test you need to risk, and the people who enter on that knows the risk. And if your risk start to make important damage you need to stop the study.
Using a commercial trademark in a study isnt good, and almost time forbidden, if really says Ritter in the study, the JAMA will not publish, but it has publish, so it is true that is said that??? And it happens all time, some industry pays a scientist to test a new drug, using the generic name and not the commercial. But then the industry use this study to sell him commercial product. Or even can change a concept of a disease to sell more.

About your methods of control BP, all right.
1 - Low Carbs, Carbs can make you fat, has a lot of calories, you can losse weight if you low carbs, but a balanced diet is more effective.
2 - Cut Salt - Great method
3 - Exercise - Great method
4 - Lose Weight - Antoher one
Do you know that you can lower more than 10-20 in you BP with this 3 methods? This is true... And many people can avoid using drugs with this.

5 - Drugs... This is very dificult to know what is good. Go to a doctor and talk is the better way. hydrocholorothiazide can lower your BP with efficienci in low doses, and dont have side effects (diabetes can be one side effect, but when used in high doses, not more good for hypertension). ACE inhibitor or ARB is good, specially for the kidneys, but Beta-blockers can be good to the heart. And Blocker of the Calcium channel can be also good. For hyperttension you have a lot of drugs and combinations. And more important, depending of the country you treat is diferent (to see how dificult is to treat some diseases). So go to a doctor to see.

And now the nice part. The study.
Have you ever enter an see the orginal article?
Go to JAMA (www.jama.com) and look for "Effects of Low Habitual Cocoa Intake on Blood Pressure and Bioactive Nitric Oxide"
You will see that even the article dont have a conclusion, they says that "Data in this relatively small sample", this means that it took few peoples to study, so you dont know if really is good. You need to study better in more people... Imagine this same reasearch in 2000 people or more??? This is what is needed to see if chocalate is good.
In the text you will see that "Regular intake of cocoa-containing foods is linked to lower cardiovascular mortality in observational studies", so someone before have noticed and the scientist was guarded by reasearchs and observations that have been realeased before. They not simple start a think in the dark. They saw some studies, think, make a study, pass in a ethic comission and then start to study, maybe used ritter because is cheapest. And more interesting in any time of the abstract they says ritter (so your source is right when says ritter? Maybe have get some secret information and released? It is really true?)
About the results. "mean (SD) systolic BP by –2.9 (1.6) mm Hg (P < .001) and diastolic BP by –1.9 (1.0) mm Hg (P < .001)" The mean of lowered was little, only 3...
And the final: how much you need to take? 6.3 g of dark chocalate or 30 kcal. The other chocolate maybe not work and eat more maybe not help. There is no study, but you can imagine. If you start to eat a lot of chocalate or eat the milk one that has a lot of fat, you eat a lot of calories and start to gain weight, and the little benefits (remeber, lowering 3?) Will not be sufficient, and you are going to make damage and even highing you BP.
Maybe I recomend chocolate for lowering BP, but only 6.3g of dark chocalate... And if you cant deal with that, is better not to start to eat chocolate, and be with the good know methods - CUT SALT, EXERCISE and LOSE WEIGHT.

I dont have a id in this blog, but i have passed looking for some stuffs and think that i need to comment. I am a medicine student. I will check this blog later if have some doubts or anything else, so i can reply.
Oh, and sorry about my english, i try my best, i am not american or from a country that spokes english.