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A question of nutrition - Part 7

Eine Frage der Ernährung - Teil 7

Q: I recently read an article entitled "Rapeseed oil for healthy cooking". Is canola oil really as healthy as olive oil and coconut oil?

A: The fact that everyone believes canola oil is the new messiah in nutrition represents a triumph of marketing over fact similar to other marketing hypes such as claims that goji berries can cure cancer and regrow hair.

Fred Pescatore, MD, author of The Hamptons Diet and one of the best nutrition experts I know, calls canola oil an "ugly" oil. "The modern methods for processing canola oil are what make canola oil so ugly," he says. The oil is removed from the seeds using a mechanical pressing process and a solvent at high temperatures, after which it is further purified, bleached and gum removed, each of these steps requiring high temperatures and chemicals. Unrefined rapeseed oil contains about 10% omega-3 fatty acids, which acquire a disgusting and rancid odor due to the high temperatures during processing. This smell must be neutralized or masked by a deodorization process and this process converts a large percentage of the omega-3 fatty acids into trans fats.

And this is the "healthy" stuff they use to replace saturated fats? even if this were not the case, rapeseed oil would be a poor choice as an oil for cooking, as you should never heat omega-3 fatty acids to high temperatures. "The rapeseed oil you usually find in supermarkets has been refined, heated and completely destroyed," says Pescatore. "Yet even some of the most sophisticated health writers write about this product as if it's healthy, when nothing could be further from the truth."

"I would never use this oil," Pescatore concludes.

I agree with him.

The truth about blood type diets

Q: Is there any truth to these so-called "blood group diets"?

A: The answer is...maybe.
I wish I could give you the short answer I gave to this question a few years ago: "Diets based on your blood type are nutritional astrology!" But the truth is that I'm not as sure as I was then that this is just hokum, even though the way many people interpret this topic is pretty garbage.

Here's a quick summary of the theory: there is a chemical reaction between your blood and the foods you eat that is brought about by a group of proteins called lectins. According to Peter D'Adamo, author of the book Eat Right for your Type, what happens when you eat foods that contain lectins that are not compatible with your blood type is that these lectins target specific organs and begin to stick blood cells together. This is not life-threatening, but it does affect your well-being.

According to Michael Lam, MD, MPH, 95% of the lectins you ingest from food are broken down by your body, but the remaining 5% are not. These remaining 5% enter your bloodstream and can have different reactions with different organs. If you've never heard of this stuff, here's the short version:

  • Type 0 is the high protein, meat-eating type.
  • Type A is the typical tofu-eating vegetarian
  • Type B and AB are mixed types who can eat almost anything

Of course, the whole thing is a bit more complicated, but these are the basics. There has been some research - including by Laura Power, Ph.D. - regarding the influence of blood type on diet, and it appears that blood type may be one of the determining factors in what foods are best for a given person. But there are more than a few caveats here.

First of all, there are more than the four blood types you read about in popular science nutrition books. In reality, there are about 20 different subgroups of people with blood type A alone. These subgroups have important differences and do not react in the same way to certain foods.

The second problem is that blood type is only one of many factors. For example, I have seen more than one type A person who felt bad on a vegetarian diet. And even if your blood type should be fine with dairy, you could suffer from a lactose intolerance that makes the whole thing irrelevant.

Thirdly, people who use blood type as a serious diagnostic tool and nutritional planning aid take far more than just your blood type into account. Naturopath and physician Dekker Weiss, NMD, a supporter of blood type theory, told me that he does all sorts of additional testing besides blood typing to figure out how to optimally personalize nutrition for the best results. My personal opinion is that using just four blood types as a basis for overall diet planning is pretty thin, and I think most supporters of this system will agree with me here. Even D'Adamo, who popularized the whole topic in the first place, offers an intensive seminar for experts to show how to use this system correctly.

And Laura Power, who did the research I mentioned, has developed what she calls the eight "biotypes" based on the blood group data. I myself like to use the blood group story as a party trick. If someone tells me they are a big meat eater and feel good with this, there's a good chance they have blood type 0. It almost always works.

Stress fighter, fatigue killer

Q: Is Rhodiola worth a try or is it nothing more than hype?

A: Rhodiola is actually quite a good thing.
Rhodiola Rosea is a plant that grows in cold climates such as the Alps and Iceland. It's known as an adaptogen, which means it can improve your mood when you're feeling low and calm you down when you're aroused. An adaptogen is like a thermostat that regulates the temperature in a home. An adaptogen is used to improve mood, reduce stress and combat tiredness and fatigue.

And the research on the subject is promising.
A review published by the prestigious American Botanical Council in 2002 concluded that numerous studies conducted with Rhodiola show that Rhodiola helps prevent fatigue and reduce stress. According to Dr. Andrew Weil, it also improves immune function and increases sexual energy.

A placebo-controlled, randomized, double-blind study examined the effects of Rhodiola on physical capacity, muscle strength, speed of limb movement, reaction time and alertness in healthy volunteers. The results documented that Rhodiola can improve endurance training capacity. (Int. J Sport Nutr Exerc Metab; 14(3): 298-307, 2004). Another study investigated the effects of Rhodiola on 40 students during a stressful exam period. The most significant improvements were observed in the areas of physical fitness, mental fatigue and neuromotor tests. Significant improvements in general well-being were also observed in the Rhodiola group. The respectable Physicians Desk Reference for Herbal Medicines says, "Rhodiola may be helpful in relieving mental and physical fatigue and improving endurance exercise performance and general well-being."

The recommended dosage is 50 to 200 mg per day. You should be careful to buy rhodiola from a source with a good reputation and not some clown from a TV commercial.


Q: In your book The 150 Most Effective Ways to Boost Your Energy, you mention Lo Han, a sweetener. What is it all about? I've never heard of this stuff before!

A: Lo Han is the name of a sweetener extract from the Luo Han Guo plant that grows in the mountains of southern China. This is also known as Luo Han Guo and Luo Han Kuo. Lo Han has a vanishingly low glycemic impact, is much sweeter than sugar - about 250 times sweeter - and can be used in both hot and cold foods, which means you can use it in baking and cooking, and you can add it to coffee or tea.

Commercial Lo Han products such as Lo Han Sweet provide around 2 kcal per serving.

From hungry to horny

Q: Are there any foods that act as aphrodisiacs?

A: I wish there was such a thing.

Beer bellies and bad foods

Q: Are there specific foods or dietary regimens that result in more fat accumulation in the belly area? And can beer lead to a beer belly as it causes fat to be preferentially stored in the abdominal area?

A: Are there foods that cause fat storage in the abdominal area? Yes: Foods with too many calories and too much sugar. Is that enough of an answer for you?

Okay, seriously, that's a good question and here's the answer. When you spike insulin levels, as you do with high-sugar foods or highly processed carbohydrates, you increase the likelihood of developing insulin resistance. Insulin resistance almost always goes hand in hand with a big, fat belly. In fact, the following is a "low-tech" test for insulin resistance: If you walk towards a wall, does your belly hit the wall in front of you? A man with an abdominal circumference of over 100 cm and a woman with an abdominal circumference of over 88 cm will almost always suffer from insulin resistance. You can alleviate insulin resistance with a low-carb diet. It's not just sugar and carbohydrates that make you fat, but they dramatically increase levels of the hormone insulin, also known as the 'fat storage hormone'.

You could eat 10,000 kcal a day in the form of coconut oil and you'd be fat as a horse, even though coconut oil contains no carbohydrates. And you can be fat as a barrel and carry most of your fat around on your back or your thighs, your hips and your butt. However, if I were trying to avoid a life preserver around my midsection, the first thing I would cut back on would be sugar and processed carbs. And as for the beer belly, although many types of beer contain massive amounts of carbohydrates, it is believed that beer may contain estrogen-like compounds that could promote fat storage around your midsection.

However, if you drink a six-pack of beer every night, the calories alone will cause you to store fat. Remember that the term beer belly wasn't chosen because the term steak belly was already taken.

By Jonny Bowden

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