Sunday, 25 May 2008

Beans beans, they're good for your heart; the more you eat the more you

Gas, flatulence, farting, tooting, breaking wind... all words that stand for the same thing- intestinal gas that escapes from “the southern route”.
We all do it- on average 10-20 times a day (although some pass gas up to 50 times a day). Women tend to pass gas less frequently than men but, according to one study*, their emissions are a bit more...aromatic.

Farts are made up of 6 gases: nitrogen and oxygen that come from swallowed air, hydrogen and methane that are produced in the intestine from friendly bacteria that lives there, and sulphur. Sulphur makes up a very small fraction of the total gas but it’s the one that causes the stink. So, because women pass less gas a day, their farts seem to contain a higher concentration of sulphur gas.

Intestinal gas comes from 2 sources:

1. Increased intake of gas (ie. swallowed air).
Swallowed air is also called aerophagia and occurs unconsciously out of habit and/or while drinking and eating. Drinking quickly, chewing gum, using tobacco, sucking candy, drinking carbonated drinks and loose dentures are all things that can increase the amount of air you swallow.

2. The breakdown of undigested foods broken down by bacteria in the intestine. Our intestines contain hundreds of different harmless bacteria in it that feed off the undigested foods we eat.
Gas-forming bacteria feed mostly off of carbohydrates and sugars:

Beans contain a high percentage of sugars- oligosaccharides- that we can’t digest and are a favourite of our friendly bacteria. Soaking beans before cooking them and then getting rid of the water will help cut down on their gas-producing power. Sadly, you lose some water-soluble vitamins when you do this.

Smaller amounts of the same sugar are also found in vegetables like cabbage, brussel sprouts, broccoli, asparagus, cauliflower and cucumbers.

Other gas-producing foods include:

Other vegetables like onions, radishes and artichokes.
Fruit, especially apples, apricots, peaches and pears.
Dried fruit, especially prunes and raisins.
Foods high in soluble fibres like oat bran, nuts and seeds.
Sugar alcohols (sugars ending in –ol, like sorbitol and mannitol) found in many diet products.
Whole grains, coffee, dark beer, red wine and fatty foods are also possible culprits.

If you don’t have the enzyme to break down certain food components, you may produce more gas when you eat those foods. For example, people who don’t have the enzyme lactase can’t break down the sugar lactose found in milk products.

Excess flatus?
If there are no medical conditions that’s causing excess gas, try limiting the amount of air you swallow by eating slower, avoiding or limiting foods that contain air- carbonated drinks, whipping cream- and try avoiding drinking from a straw, chewing gum, smoking and get dentures that fit well.

You can also try eliminating gas-producing foods. This requires some trial-and-error. Any of the gas-producing foods can be removed from the diet one group at a time, for a minimum of a week at a time, until you feel relief.

There’s a product called Beano on the market that contains an enzyme called alpha-galatosidase (extracted from mold!) that helps break down the complex sugars in many gassy foods.

However, most experts will tell you that you shouldn’t "give a hoot that you toot”- it’s perfectly normal.

Smelly flatus?
The gas produced by bacterial fermentation can smell, depending on the food eaten. Suggestions include limiting common culprits such as garlic, onions, spicy foods and beer.

Loud flatus?
This is caused by the muscles of the bowel forcing air through the tight ring of muscle at the anus. Suggestions include passing the air with less power and reducing the amount of intestinal gas by making dietary adjustments.

*Farting study- thought it was worth including the procedure! Volunteer producers -- primed by a diet of pinto beans -- farted into aluminum bags via a rectal tube. The contents of the bags were measured for volume and for sulphur concentration. (Sulphur gases give farts their foul odour.) Syringes full of gas were withdrawn from the bags and wafted by the nostrils of the unfortunate judges. Fun job!

Leyner M, Goldber B. Why do men have nipples? Three River Press. 2005.

Thursday, 22 May 2008

Does your pee stink after eating asparagus?

After eating asparagus, some people's urine has a very distinct, stinky smell.

Asparagus contains a compound called mercaptan. The smelly pee is a result of this compound being broken down in your digestive system. However, not everyone has the gene for the enzyme that breaks down mercaptan. One British study found that 46% of British people tested produced odour after eating asparagus.

Another study of a random sample of 115 people showed that 40% had stinky pee after eating asparagus and they determined that it's inherited through an autosomal dominant inheritance pattern. Interestingly, another study found that all the subjects broke down mercaptan, but their ability to smell it in the urine differed. Those who were able to smell the odour in their own urine could smell it in the urine of anyone who had eaten asparagus irrespective of whether or not that person could smell it. The authors suggested that the ability to smell the stinky urine is also genetically determined.

So are we all stinkers, but only some of us smellers? Not exactly. People, like myself (too much information?!), don't break down mercaptan (so are non-stinkers) but can smell it in other people's urine. Conversely, some people who break down the compound (stinkers) were unable to detect the smell in urine others had identified as outright putrid.

Don't worry, even if your urine smells after eating asparagus, it's not a bad thing and definitely not a reason why you should avoid asparagus. Asparagus is great source of folic acid, thiamin, vitamin B6, fibre and
one of the richest sources of rutin, a compound that strengthens capillary walls.

So... are you a stinker?

Leyner M, Goldberg B. Why do men have nipples? NY: Three Rivers Press. 2005.

Wednesday, 21 May 2008

Coffee with breakfast spikes blood glucose

A new Canadian study just appeared in the American Journal of Clinical Nutrition and is getting a bit of press. Participants were non-diabetic men, aged 18-50 (average age was 23) with a BMI between 19-29 (average was 25).

The men were either given caffeinated coffee or decaf coffee 1 hour before their breakfast. The ones that received caffeinated coffee were given an amount of Maxwell House Original Roast that provided an equivalent of 5 mg caffeine/kg. The average weight of the participants was 78.5kg so they got an average of 390mg caffeine* or about 2.5 cups of this coffee (which had 62g caffeine/100mL). The decaf group received an equivalent volume of decaf.

The participants were then given either a high glycemic index bowl of cereal – Crispex- or a low glycemic index breakfast- All Bran- with the same amount of milk. The amount of cereal was calculated so that both meals provided 75g carbohydrates.

The subjects were randomly placed in all 4 groups with 1-2 weeks between them. 2 days before each trial, subjects were asked to not drink any caffeinated or alcoholic beverages or do any strenuous exercise.

As expected, blood glucose rose after they ate either meal. What was surprising, however, was that blood glucose rose significantly higher when the participants had the caffeinated coffee versus decaf- regardless of whether they had the low GI or high GI meal. At the same time, the caffeine made the people more resistant to insulin, causing their blood glucose to rise higher.

According to the researchers, this is no big deal for healthy, non-diabetic people since their blood sugar will get back to normal automatically. However, they point out that “caffeine should be considered a dietary risk factor for blood sugar control” for people with diabetes and, as a result, they would benefit from drinking decaf coffee.

In my opinion, more research has to be done. There were only 10 participants, all men, enrolled in this study and none of them had diabetes. What would be the effect in people that were actually insulin resistant? Moreover, we all know caffeine affects everybody differently, especially if you're not used to having it. 2 of the 10 participants didn't normally drink coffee and the others were light to moderate caffeine consumers. This should be controlled in future studies.

If you do have diabetes, test your blood sugar before your meal and 2 hours after and check to see if there's a difference whether you drink decaf versus caffeinated coffee.

*Health Canada recommends an intake of less than 400mg caffeine/day, but <300mg class="MsoNormal">Sources: Moisey LL, Kacker S, Bickerton AC, Robinson LE, Graham T. Caffeinated coffee consumption impairs blood glucose homeostasis in response to high and low glycemic index meals in healthy men. Am J Clin Nutr 2008; 87:1254-61.

Wednesday, 14 May 2008

Exercising at a younger age helps prevent breast cancer

In 2007, a study was published showing that women 20-69 years old who reported doing 6 or more hours per week of strenuous exercise had a 23% reduced risk of invasive breast cancer compared to sedentary women,

A recent study has just shown that women between the ages of 12 and 35 who exercise regularly are 23% less likely to get breast cancer before menopause than less active women. The women with the lowest risk reported either running 3.25 hours a week OR walking 13 hours a week.

A quarter of all breast cancer cases are diagnosed before menopause.

This new study is the largest study so far on pre-menopausal breast cancer. 65 000 women completed questionnaires on their level of physical activity at various periods of their lives, starting from age 12. The researchers followed up over six years and found that 550 women had been diagnosed with breast cancer.

The researchers concluded that the benefits of exercise weren’t linked to a particular sport or intensity, but to the total activity.

Both this study and the 2007 one speculate that women who are more active have a lower breast cancer risk because they tend to menstruate later in life and are therefore exposed to less estrogen. Women exposed to more estrogen have a greater breast cancer risk.

Bottom line: it’s important for girls to start being more physically active early on- in their teens and early adulthood- to help reduce their risk of developing breast cancer. Of course, being more physically active can also help prevent obesity and it’s complications- type 2 diabetes, heart disease, high blood pressure.

Sources: , ,

Psychological stress associated with overeating

Dr. Mark Wilson and his team at Emory University recently published their study that sought to observe the relationship between diet and exposure to psychologically stressful environments.

Female rhesus macaques (rhesus monkeys) organize themselves and maintain group stability through continual harassment and threat of aggression. Obviously, this situation is an important source of chronic stress for the monkeys that are the recipients of this aggression.

The researchers looked at the feeding patterns of the aggressive, dominant monkeys compared to the socially subordinate monkeys and found that the dominant females ate significantly less food than the subordinate monkeys. As a result, the stressed-out subordinate females gained more weight and had a higher level of the stress hormone, cortisol, a hormone that seems to be responsible for abdominal storage of fat. Fat that’s stored around the abdomen is called visceral fat and is more dangerous and associated with an increase risk of heart disease and type 2 diabetes.

This study provides important insight into the psychological basis for the sharp increase in obesity in recent years.


Emory University (2008, May 14). Psychological Stress Linked To Overeating, Monkey Study Shows. ScienceDaily. Retrieved May 13, 2008, from­ /releases/2008/05/080513125216.htm

Yale University (2000, November 23). Stress May Cause Excess Abdominal Fat In Otherwise Slender Women, Study Conducted At Yale Shows. ScienceDaily. Retrieved May 14, 2008, from­ /releases/2000/11/001120072314.htm

Friday, 9 May 2008

Square watermelons...of course.

Watermelons are big and round and take up a lot of room in the fridge, right? They’re also difficult to cut because of their shape.

To solve this problem, innovative Japanese farmers started growing square watermelons in 2001. It’s just more practical- they take up less space!

While the fruit is growing on the vines, they insert the melons into square glass cases.

The square watermelons are expensive though- they sell for 10 000 yen or ~82$. Normal watermelons sell for 15-25$ each in Japan.


Wednesday, 7 May 2008

What about stevia?

Stevia is a plant that’s in the sunflower family and is native of Paraguay. It’s 300 times sweeter than sugar without the calories.

The people of Paraguay and Brazil use it to make sweet herbal tea and it’s been adopted by Japan that uses it in various products including soy sauce and sweet pickles. It’s also found in their Diet Cokes. Rebiana is the trade name for a patent-pending sweetener developed by the Coca-Cola Company, jointly with Cargill.

Stevia claims to strengthen the immune system, enhance the body’s natural production of vitamins, promote regularity, support liver health, help control the formation of free radicals, nourish the pancreas, be an excellent weight loss aid, help minimize hunger sensations, reduce cravings for sweets and fatty foods, aid in digestion, decrease hypertension, stabilize blood glucose levels, shorten recovery time from cold and flu and aid in addictions to tobacco- wow!

Agriculture Canada is currently growing the plant to determine the feasibility of growing the crop for commercial purposes. Coca Cola also plans to obtain approval for Rebiana as a food additive within the US by 2009.

Good luck since stevia is actually banned in the European Union, Singapore and China. Australia, New Zealand, Canada and the States forbid the use of stevia in foods. In Canada and the States, it can only be sold in health food stores as a dietary supplement (things sold in health food stores don’t have to be approved by Health Canada or the US Food and Drug Administration).

Once upon a time, stevia could be found in foods in the US, like in Celestial Seasonings herbal tea. However, in the early 90s someone tattled to the FDA, pointing out that stevia had not been approved- rumour has it that it was Monsanto (aspartame manufacturer) that blew the whistle...

So why is stevia banned in so many places? There’s lack of proof that it’s safe. The Centre for Science in the Public Interest (CSPI) has placed it in their ‘everyone should avoid’ category. High doses fed to rats reduced sperm production and increased cell proliferation in their testicles, potentially causing infertility. There’s also a possibility that it may be a carcinogen.

The CSPI states that “small amounts are probably safe”. A member of the CSPI pointed out that: “it may be that with further experiments and further research we'll find that stevia would really not be a problem in the amounts that consumers would be consuming but right now the record shows stevia shouldn't be approved yet until there's more research."

I choose to stay away from it... but it’s your choice.

Centre for Science in the Public Interest Health Letter. Nutrition Action. “Chemical Cuisine: A guide to food additives. May 2008.
Nestle, Marion. What to Eat. North Point Press. 2006.

Tuesday, 6 May 2008

The saltiest meal in America

In case you missed it, frequent reader of this blog, Mike, posted a link in the comments of my previous sodium blog to a report done by Men's Health Magazine on the 20 saltiest foods in America (thanks Mike!).

I thought it was worth posting some of their entries.

Remember that adults should be aiming for 1500mg sodium a day and not more than 2300mg/day.

Saltiest bread: Dunkin' Donuts Salt Bagel at 4520 mg sodium, 320 calories.

Saltiest Salad: Romano's Macaroni Grill Chicken Florentine at 5460 mg sodium, 840 calories.

Saltiest Kid's Meal: Cosi Kid's Pepperoni Pizza at 6405 mg sodium, 1901 calories. The recommended sodium intake for children over 9 years old is 1500mg and for kids 4-8 years old, it's 1200mg/day.

Saltiest appetizer: Papa John's Cheesesticks with Buffalo Sauce at 6700 mg sodium, 2605 calories.

Saltiest Pizza: Pizza Hut Meat Lovers' Stuffed Crust Pizza ( 3 slices of a 14" pie): 5070 mg sodium, 1560 calories.

Saltiest dessert: Atlanta Bread Company Raspberry Scone at 1750 mg sodium, 360 calories.

And drum roll please…..

Saltiest dish in America: Romano's Macaroni Grill Chicken Portobello at 7300mg sodium, 1020 calories.

Sunday, 4 May 2008

Everyone should avoid sweeteners...

So, I just received the newest edition of the Centre for Science in the Public Interest’s (CPSI) newsletter, Nutrition Action. They have listed common food additives and their assessment of their safety, categorizing them as Safe, Cut Back, Caution, Certain People Should Avoid and Everyone Should Avoid.

Interestingly, under the category of “Everyone should avoid” are sweeteners: Aspartame, Acesulfame-Potassium and Saccharin.

This is their reasoning:

A new Italian animal study found that long term use of aspartame (marketed as Equal and found in soft drinks ), in amounts similar to that found in the human diet and below the acceptable intake deemed safe by Health Canada and the States, could increase the risk of leukemia, lymphoma and breast cancer.

The CPSI points out that studies done on Acesulfame-Potassium (Acesulfame-K- found in diet soda and foods) in the 70s showed a link between the sweetener and cancer and the US FDA hasn’t required better research since.

They also point out that animal studies have shown that Saccharin (Sweet n’ Low) can cause cancer of the bladder, uterus, ovaries, skin and other organs. A US National Cancer Institute study found that people that ate large amounts of saccharin had higher rates of bladder cancer than people who used smaller amounts. The use of saccharine in foods and drinks is illegal in Canada but Sweet n' Low is sill around.


CPSI Nutrition Action Health Letter “Chemical Cuisine: A guide to food additives”. May 2008.