Low fat diet and ovarian cancer

You may have read a lot lately about a new piece of published research "showing" that a low-fat diet reduces the risk of ovarian cancer.

Here's what happened.

Researchers studied two groups of women. The first group- about 19,500 women- were assigned to a "low-fat" regimen complete with 18 group sessions of behavioral modification in the first year, and 4 sessions a year after that. They carefully recorded their food intake.

The second group- about 29,000 women- ate their "regular" diet. Which turned out to be, by the way, about 10 percent higher in fat. There was one other difference between the two groups, but I'll save that for later.

In all other areas- age, race, BMI, exercise- the two groups were statistically matched.

For the first 4 years of the study there were no differences in cancer rates.

For the second 4 or so years, women on the first diet- which researchers called the "low-fat" diet- had a 40 percent reduction in risk for ovarian cancer. Now understand what that means. It does not mean 40% of the women did not get cancer. In the second ("regular diet") group, the percentage of women who actually got ovarian cancer was .003 (that's 3/1000). The percent in the so-called "low-fat" group was .002 (that's 2/1000). From a percentage point of view that's a 40% reduction but it's pretty damn thin when you look at what it really means. (Remember, an increase from 1 in a million to 2 in a million is a 100 percent increase!)

So in fact, 103 women in the "regular diet" group got cancer, and 57 in the so-called "low-fat" group did. Percentage wise that's nothing (3/1000 vs 2/1000 of a point) but if you're one of the extra 46 women, it's pretty darn significant.

But remember I told you there was one other difference between the two diets?

Here's what it was: The "regular diet" people ate on average one less serving of fruits and vegetables per day.

So what I want to know is this: Why in the world would you attribute that small difference in ovarian cancer to a tiny difference in total fat intake and NOT attribute it to the power of even a single serving of fruits and vegetables?

From this data, it is just as possible to conclude that even one serving of fruits and vegetables a day has a powerful enough effect to prevent 40 out of 29,000 women from getting ovarian cancer.

That makes way more sense to me than attributing it to a tiny reduction in fat. Vegetables and fruits have anti-cancer properties. Fat does not have "pro-cancer" properties, at least not when it's in the diet. (When it's on your body, maybe, but that's a completely different issue, though many people confuse them.)

This study shows nothing more than the fact that if you start out believing something (low-fat diets are great) you can find something in the data to support it.

And that the headline "one extra serving of fruits and vegetables a day can reduce cancer risk" isn't quite as sexy as the "low-fat" diet stuff.

high glycemic diets and blindness

Consuming higher-than-average amounts of carbohydrates that cause blood sugar levels to spike and fall rapidly could be a risk factor for central vision loss with aging. Scientists supported by the Agricultural Research Service (ARS) and grants reported the findings this year in the American Journal of Clinical Nutrition.

ARS is the U.S. Department of Agriculture's chief scientific research agency.

The study was led by Chung-Jung Chiu with Allen Taylor, both at the Jean Mayer USDA Human Nutrition Research Center on Aging (HNRCA) in Boston, Mass. Taylor is director of the Laboratory for Nutrition and Vision Research at the HNRCA.

The researchers analyzed dietary intake and other data from more than 4,000 men and women aged 55 to 80 participating in the Age-Related Eye Disease Study, or AREDS.

Diets high in carbohydrates that are quickly digested and absorbed, resulting in a rapid rise in blood sugar levels, are considered high-glycemic-index diets. Examples of such "fast carb" foods are white bread, rice, potatoes and pasta, and also sugars and corn syrups. Carbohydrates leading to a more gradual rise and fall in blood sugar levels comprise low-glycemic-index diets.

Though "slow carb" foods are often listed as whole-grain versions of bread, rice and pasta, truth be told a lot of these foods have just as high a glycemic load as their processed breatheren. For example, "whole wheat macaroni" has a pretty high glycemic load of 17, while regular old junky "enriched" macaroni has a slightly lower glycemic load of 16. Check the glycemic load of any food on the Nutrition Data Website . (Remember, numbers don't exist for every single food, but they do for most carbohydrates, which raise blood sugar the quickest.)

Central vision loss is one of the first signs of age-related macular degeneration (AMD), a disease that is one of the leading causes of blindness among the elderly.

Consuming a diet high in fast carbs is also suspected of being involved in the vision loss that sometimes occurs in people with diabetes. The researchers theorize that the type of damage to eye tissue produced by fast carbs could be similar in both AMD and diabetic eye disease.

At this time, there is no effective cure for AMD, so finding modifiable risk factors is important. While it's too soon to recommend dietary slow carbs as a preventive strategy for AMD, replacing fast carbs with whole grains may soon prove to be an early dietary intervention to slow its progression.

Source: USDA Agricultural Research News Service

Toxic Marriage is bad for the Heart

Women who swallow their anger during fights with their husbands are statistically more likely to die of heart disease than women who say what's on their minds. University of Utah scientists studied 150 married couples, videotaping them while they discussed "sensitive" topics from money management to who's going to do the dishes. Their conversational styles were telling. Wives whose men dominated the conversation, making cutting nasty remarks while the wives sat in silence, were far more likely to show high levels of coronary calcification, a signal that heart disease is in the making.

Interestingly, if the conversations turned into an open battle for control (as opposed to a more cooperative discussion about how things could be made better), the men showed more evidence of heart disease. The men did not, however, show any negative effects from the "self-silencing" strategy that was so harmful to the women.

Meanwhile, in a completely different paper published in the Archives of Internal Medicine, researchers studying over 9,000 British civil servants found that those with the worst close relationships were 34% more likely than those with good relationships to have heart attacks or other heart trouble during 12 years of follow-up.

So what does this tell us? Several things. One, strategies (sitting silently during an argument) may be far more stressful for some people (or for one of the sexes) than for others. Two, relationships can make you sick (or keep you well—other studies show that married folks live longer than single ones). Three, there's no divide between body and mind. What happens in your head affects your physiology, and what happens in your physiology affects what happens in your head. It's an open loop, and the "division" between mind and body is completely fictional.

In workshops, I'm fond of telling the story about a famous study done in a nursing home. In this study, half the participants were given a plant to take care of and the other half weren't. The ones who were given the plant to take care of had better health outcomes, less illness, better blood tests. That fits nicely with the idea that staying connected—even to an inanimate object—and putting some attention on something outside yourself has health benefits.

Relationships matter. It may seem obvious but science is sometimes about demonstrating things we already know intuitively. Recently a study by Shira Feldman at the University of Minnesota School of Public Health showed that kids who regularly sit down to a family meal are at lower risk for smoking, drug and alcohol use. According to Tara Parker Pope in the NY Times, children from "highly connected" families have been shown to eat healthier foods, get better grades and have lower risk for destructive behaviors.

A health program that concentrates only on the vitamins in your diet, the number of miles you walk, or (God forbid) the amount of fat you eat is missing one of the biggest contributors to overall health in the world: your connectedness to others.

Connectedness counts. It matters to the people around you—and it definitely matters to you.

Your health depends on it.

Low Fat Diet and Ovarian Cancer: Don't jump to conclusions

A new study published in the Journal of the National Cancer Institute has been touted in the media as showing how a low-fat diet can reduce the risk for ovarian cancer. But the results are a little more iffy than you might have been lead to believe.

First, what happened: According to data from the Women's Health Initiative Dietary Modification trial, women who decreased the amount of dietary fat they consumed were 40% less likely to develop ovarian cancer than women who followed "normal dietary patterns". Thinking readers will quickly see some problems with this conclusion. Here are just some of them.

It's not possible to "reduce" one part of the diet (fat, carbohydrate, protein) without affecting the proportion of calories coming from the others. If a diet is low in fat, it's got to be higher in something else. This is true for all dietary studies like this one. It's also possible—and very likely—that when people follow what they think is "healthy" advice (like eat less fat), they are also more likely to do other things that can have health benefits (like stop smoking, or eat more vegetables, or exercise more). There's no way to account for how much the results are due to outside factors (what researchers call "confounding variables") like these.

In addition, more than a little research has shown that even when people are counseled to "eat less fat," and even when they are given a target goal, and even when they actually follow the target goal in the beginning (three very large "ifs") eventually their fat intake starts to look suspiciously like the one they started with. In this particular study the women were counseled to eat 20% fat, but by the end of the first year they were in fact up to 24%, and by the end of the study, 29%.

Most important, the "fat reducing" women also increased their consumption of fruits and vegetables, and there's absolutely no way to know whether their lower rate of ovarian cancer had to do with the reduced fat or the increased anti-cancer compounds, anti-inflammatories and anti-oxidants from the plant foods. Ask me, I'm guessing the latter.

Walter Willet, MD, the chairman of the Department of Nutrition at the Harvard School of Public Health and arguably the most important nutritional epidemiologist of our time, has said of his own monumental "Nurses Health Study" that the percentage of fat in the diet has shown no relationship to any major health outcome. However, the type of fat (trans fats, for example) and the type of carbohydrate (sugar, processed carbs), does.

There's no doubt that obesity puts you at increased risk for a host of diseases, including some cancers. This may turn out to be because the fat cells are mini-endocrine glands that secrete all kinds of hormones that can be problematic for some cancers (including estrogen). But fat on the body isn't the same as fat in the diet. Once we get over the idea that "fat makes you fat" and realize that insulin makes you fat, and carbohydrates—especially processed carbs—drive up insulin, we'll begin to concentrate on the real culprits in our diet: Sugar, processed carbs and junk food.

Fat—not so much.

Mercury, fish and you: What to do?

Want to see the law of unintended consequences in action? Watch this:

1. We know that mercury is a neurotoxin and a really bad thing to be ingesting (at any time, but especially when you're pregnant)



2. We know that coal burning plants deposit way more mercury into the environment than is good for anyone's health, and that people are consuming this stuff through their food, including - and maybe even especially - fish



3. Conclusion: Warn people not to eat too much fish

It was an advisory that was well-meaning and well-intentioned. But it turns out to have been a really bad idea. And now, a coalition of nutrition experts - including a few federal agencies - is challenging government warnings that pregnant women limit their fish consumption. "The intent of the FDA advisory was a good idea" agreed Roger B. Newman, MD, director of obstetrics at the Medical University of South Carolina and a spokesman for a group called the Maternal Nutrition Group. But then he added: "The unintended consequence has really been a major health issue."

Here's the problem: People listen in sound bytes. Mention mercury, neurotoxin and fish in the same sentence and people remember the three word take-away "fish is bad". And more than a few people - including pregnant women - are staying away from it in droves. But a powerful new study by Joseph R. Hibbeln, MD and his colleagues in the US and UK indicates that this is the exactly wrong strategy if you want your newborn to be smart and healthy.

After adjusting for over 25 different factors including social class and breastfeeding, Dr. Hibbeln's team found that children born to mothers who ate more seafood than the current US guidelines for pregnant/nursing women (12 ounces per week) had higher tests on fine motor, communication and social skills, showed better social behaviors and were less likely to have low verbal IQ scores at age 6.

In contrast, children of mothers who ate no fish were:

• 28% more likely to have poor communication skills at 18 months



• 35% more likely to have poor fine motor coordination at age 3 1/2 years



• 44 % more likely to have poor social behavior at age 7 years



• and 48% more likely to have a relatively low verbal IQ at age 8

Furthermore, Hibbeln's team recorded no evidence to lend support to the warnings of the US (fish and mercury) advisory that pregnant women should limit their seafood. Other studies - namely the famous Seychelles Study, which studied 700 children in the Seychelles Islands - have also found absolutely no evidence of damage to children whose mothers ate about 10 times as much fish as the average American, fish that were generally higher in mercury content to boot. (Let's also not forget that fish is high in selenium, which helps to chelate mercury in the first place).

Meanwhile, the benefits of fish eating are enormous, and many of these benefits are being lost to people who are being scared away from fish by the warnings. Eating fish lowers the risk of death from cardiovascular disease by 36% (according to a study in the Journal of the American Medical Association in Oct. 2006), and omega-3's from fish are associated with improvements in behavior, cognition, heart health, brain health and mood.

The warning against pregnant women eating the four types of fish most contaminated - shark, swordfish, king mackerel, or tilefish - should stand. But let's remember that warning is for pregnant women and nursing mothers, and doesn't apply to the rest of the population. Plus let's also remember that the mean mercury concentration for fish like salmon, haddock, atlantic or pacific mackeral, sardines, scallops is generally less than 1/10th the amount found in the "big four". Plus you can avoid the whole issue by buying from reputable wild fisheries like Vital Choices, which is featured on my website.

Part of the problem with the advisory is in the language. The 2004 advisory from the EPA and the FDA suggests "limiting" fish to 12 ounces (about 2 meals) per week. Representatives of the Maternal Nutrition Group, as well as Healthy Mothers Healthy Babies Coalition are urging a minimum of 12 ounces a week. I agree totally. The change in emphasis could produce a health-boosting change in behavior. "There's always a benefit to women eating more than 12 ounces of fish per week," said Dr. Hibbeln.

Incidentally, no one is more anti-mercury than I am, and no one wants to see tighter regulations and a global initiative to cut down on emissions. But as a point of information, most of the methyl mercury in ocean waters comes from forest fires, undersea volcanoes and geothermal vents, not from coal burning power plants, though such plants do pollute nearby lakes and rivers, do increase our exposure to this neurotoxin, and do account for a very small portion of the methyl mercury in oceans.

Sure let's get rid of the mercury. But let's not throw out the baby with the bath water. And in this case, the example is more than a metaphor.

Gary Taubes, Good Calories Bad Calories

I'm 2/3 through reading my friend Gary Taubes new book, "Good Calories, Bad Calories" but I'm so psyched and fired up about it I wanted to post my "early review" even before I finish it. It's hands down the most important nutrition book of the past twenty years. It's part nutrition, part nutrition research, part sociology, part politics, part medical detective story and all absolutely fascinating reading and I'm hoping it gets the attention it deserves. This is truly what Thomas Kuhn, the philosopher of science, was talking about when he created the term "paradigm shift".

Taubes' book is beginning to get some attention. For a fast, easy read that will give you a flavor for what's going on here, don't miss this articlecalled "Diet and Fat: A Severe Case of Mistaken Consensus".

You'll be hearing more from me- and I hope many many others- about this amazing book. Meanwhile, read the Times article.

Remember, sacred cows make the best burgers.

Get ready to eat.