Chew gum, snack less?

The study:

115 men and women who regularly chew gum visited a lab at Louisiana State University's Pennington Biomedical Research Center on 2 occasions:

On the first, they were given a lunch and then stayed for 3 hours, chewing Extra® sugar-free gum for 15 minutes, once an hour.

Hunger and cravings were assessed with the help of questionnaires and at the end of the 3 hours, subjects were given a variety of snacks to choose from.

The next visit was exactly the same, but they weren't given chewing gum.

The result:

When subjects chewed gum, they reported significantly less feelings of hunger and cravings for sweet foods and felt significantly less sleepy.

Gum chewers also ate significantly less calories after the 3 hours: 40 calorie less but, more interesting to the researchers, 60 calories less from sweet snacks.

According to Paula Geiselman, Chief of women's health and eating behaviour and smoking cessation at Pennington, this is the first study to look at the nutrient composition of snack food choices following gum chewing.

What I think:

First of all, 40 or 60 calories doesn't sound like a lot. In fact, it's the equivalent of only 4-6 jelly beans. Nonetheless, that could lead to a 4-6 lbs weight loss a year if it was kept up daily.

However, I wonder if these study findings be the same if the subjects weren't regular gum chewers?

Maybe regular gum chewers that can't chew gum for 3 hours need to keep their mouths occupied and eat more (and have more cravings) whereas people that don't normally chew gum wouldn't have the same problem... In that case, wouldn't it be better to tell people never to start chewing gum in the first place?!

Measuring this only on 2 controlled occasions i very limiting too. For example, the subjects obviously knew the difference between their 2 visits was the gum chewing.

Clearly this is something that needs to be studied way more before any recommendations can be made.

Oh. Did I mention that the study was funded by the Wrigley's Science Institute? Hm.

Want to lose weight? Don't rely on chewing gum!

Stevia/Truvia/PureVia's Safety

About this time last year I blogged about Stevia. Stevia is a plant native to South and Central America and its extracts are 300 times sweeter than sugar without the calories of sugar. This time last year, the use of Stevia in food was banned in Canada and the United States because of a lack of evidence that it was safe.
However, in December 2008, the American FDA approved rebaudioside A, the sweet extract of the stevia plant, a move that has been called "President Bush's parting gift to the soda industry". Canada and the European Union have not approved the use of Stevia in food.

What changed?

The FDA received two notices that rebaudioside A was 'Generally Recognized as Safe' (GRAS). Who submitted these GRAS notices?
Two corporate giants with evident interest in using the stevia extract: Cargill Inc and Whole Earth Sweetener.
These GRAS notices informed the FDA that their ingredients were safe and didn't need pre-market approval... leading to, according to a review prepared for the Center for Science in the Public Interest (CSPI), the following products being rushed to market too early:

Truvia- from Coca-Cola and Cargill- a tabletop sweetener. Moreover, Sprite Green (from Coca-Cola) is out on the market already and Coca Cola plans to use it in Coke soft drinks and plan to release new Odwalla juice drinks with the sweetener.

PureVia- from Pepsi-Cola and Whole Earth Sweetener- a tabletop sweetener. Pepsi Co has released Trop50 (Tropicana) containing the sweetener and will launch at least 3 new flavours of SoBe Lifewater.

SweetLeaf- Wisdom Natural Brands started selling SweetLeaf sweetener.

Why the concern?

Firstly, the research was industry-sponsored raising questions about the objecticity of the science - authors of the studies are scientists from Cargill and Coca-Cola (or paid by Cargill). The FDA did not follow-up.

Some independent studies have found that the stevia extracts caused mutations, chromosome damage or DNA breakage. Although in 2 studies in which one of the extracts, stevioside, was added to drinking water and fed to rats for 2 years, there was no increase in tumors. However, the most popular extract, rebaudioside A (TruVia and PureVia are 95% rebaudioside A), wasn't tested!
Furthemore, Stevia was only tested on one animal and usually, it should be 2.
Other reports found ill effects to the rats' reproductive systems: male rats fed high doses of the stevia exract for 22 months had lower sperm production and femal hamsters had fewer and smaller babies. However, a Cargill-sponsored study found no evidence of reproductive problems through 2 generations of rats fed very large doses of the stevia extract.
Evidently, more research is waranted but, according to a senior nutritionist at CSPI, there was probably a lot of pressure put on the FDA to approve the new sweetener.

The Stevia products are being marketed as natural because they come from a plant. To underline their natural claims, the stevia products are packaged in green. However, be aware that stevia is also being blended with other sweeteners: the makers of Splenda just introduced Sun Crystals, a mix of sugar and stevia. Stevia is also being added to some soft drinks containing aspartame.

Japanese manufacturers have been using stevia since the 70s but they don't consume nearly as much soda as North Americans.

Bottom Line:
According to the CSPI, the occasional use of a stevia product to sweeten your tea or coffee is probably safe (although taste is another matter as it has been said that there is a bitter aftertaste). However, until more reserach is done, there's no way to tell whether larger amounts will increase the risk of cancer (If Coke and Pepsi add stevia to their diet drinks, millions of people will be exposed to large amounts...) .
The general recommendation when it comes to sweeteners is to limit your intake to 2-3 sweetener-sweetened products a day.
For more general information on sweeteners, click here.

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.

Sources:
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.
http://www.cbc.ca/consumers/market/files/food/stevia/
http://en.wikipedia.org/wiki/Stevia

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.

Sources:

CPSI Nutrition Action Health Letter “Chemical Cuisine: A guide to food additives”. May 2008.
http://www.nytimes.com/2006/02/21/opinion/21tues4.html

Sweeteners

So lots of stuff about sweeteners in the news so I'm going to talk about them some more...

The study everyone's talking about is one that fed 1 group rats a liquid sweetened with normal sugar and the other group with a liquid sweetened with saccharin.
After 10 days of exposure, the rats were allowed to eat a high-calories chocolate-flavoured snack. The saccharin group ate more and gained significantly more weight than the sugar group.

They also found that rats that were accustomed to eating the sweetener didn't have a temperature change after eating- normally, body temperature should rise after eating.
They suspect that that could mean that the rats' appetite control mechanism was disrupted as a result of consuming sweetener, possibly leading to them overeating.

Their theories/interpretations of their results, in a nutshell, are:

1. Artificial sweeteners may disrupt the body's natural ability to 'count' calories based on the food's sweetness. Early in life, our bodies learn that sweet foods and dense foods have more calories. It's
a Pavlovian type of behaviour. Sweeteners impair this natural relationship. The body may be fooled into thinking a product sweetened with sugar has no calories. As a result, people become unable to regulate their food intake... and therefore, their weight.

2. Liquids, diet or not, are not as satisfying as solid food.

Challengers of this study (like the Calorie Control Council that represents companies that sell artificial sweeteners!), say the research oversimplifies the complex issues that contribute to obesity in humans and lots of studies have shown that artificial sweeteners can help with weight loss.
The researchers point out that the increase consumption of artificial sweeteners is not the sole cause of obesity, but it can be a contributing factor.

Other challengers say that the study was done on rats, not humans. True. However, other studies done on humans have shown a link between artificial sweeteners and weight (see previous blog). The researchers do point out that the results need to be replicated on humans. They also want to look at whether age and gender are contributing factors...
I would like to point out though that in 1958, in the US, Congress passed the Delaney amendment to the food and drug laws which required the FDA to ban any substance from the food supply shown to cause cancer- in people or animals and even rats.

Challengers also point out that saccharin is banned in Canada. True. However, researchers say that the results would apply to other artificial sweeteners .
Supposedly, Canadian officials are reviewing the restriction on saccharin in light of new research showing it may not be harmful to humans... not sure about that one though. In 1977, saccharin was banned in the US because it was shown to cause bladder cancers in mice and rats. However, the Calorie Control Council launched a huge publicity 'freedom of choice' campaign and, Congress allowed saccharin back on the market. Interestingly, it cost 6% less to sweeten cola with saccharin versus sugar at that time... hmmm.

These are the sweeteners that Health Canada has approved for use and some comments:

1. Aspartame (Equal, NutraSweet, Sugar Twin, Sweet n' Low, also added to foods). According to Health Canada, safe for use in pregnancy. Acceptable Daily Intake (ADI): 40mg/kg body weight per day. One can diet pop= 200mg. So, a 110lbs person can safely have 2000mg a day= 10 cans Diet Coke/day. Flavour may change when heated.

2. Acesulfame-K (Added in packaged foods and beverages). Safe in pregnancy. ADI= 15mg/kg body weight/day. One can diet pop sweetened with acesulfame-K=42mg. A 110lbs person can safely have 750mg per day = 18 cans Diet Coke/day.

3. Cyclamate (Sugar Twin, Sweet n'Low, Sucaryl). Avoid when pregnant. ADI= 11mg/kg body weight/day. One packet Sugar Twin=264mg. A 110lbs person can safely have 550mg per day = 2 packets/day.

4. Saccharin (not allowed to be added to foods and beverages but available in tablets as Hermesetas). Avoid when pregnant. ADI= 5 mg/kg body weight per day. One tablet Hermesetas has 12 mg saccharin.

5. Sucralose (Splenda, also added to foods and beverages). Can be used for baking or cooking. Safe in pregnancy. ADI= 9mg/kg body weight per day. One packet of Splenda contains 12mg and 1 cup Splenda has ~250mg. A 110lbs person can safely have 450mg sucralose per day. Interestingly, Whole Foods Market refuse to sell products containing sucralose since it's not metabolized in the body and could be potentially unsafe. The products goes against the company's philosophy of selling "the highest quality natural and organic products available".

Bottom line: A healthy diet should not rely on soft drinks- diet or not- or sweeteners.

I'll have a burger, fries, a diet soda and a heart attack, please

Researchers have found another reason to cut back on red meat, fried foods and diet soda. Wait, diet soda?!

The Atherosclerosis Risk in Communities (ARIC) study, funded by the National Heart, Lung and Blood Institute, studied the food intake (using a 66-item food frequency questionnaires) of 9514 people aged 45-64 years old for at least 9 years.

In general, a Western-diet that was heavy on refined grains, processed meats, fried food, red meat, eggs and soda and light on fish, fruit, vegetables and whole grains, was associated with an 18% increased risk for metabolic syndrome, even after adjusting for smoking, physical activity and caloric intake.

Metabolic syndrome is a cluster of heart disease risk factors that include:
a high waist circumference, high blood pressure, high triglycerides, low "Healthy" HDL cholesterol and high fasting blood glucose levels. Having 3 or more of these risk factors increases greatly your risk of developing heart disease and diabetes.

The adults who ate 2 or more servings of meat a day increased their risk of developing metabolic syndrome by 25% compared to those that ate meat twice a week or less.

Fried food was also associated with a higher rate of metabolic syndrome, as was diet soda. Risk of developing metabolic syndrome was 34% higher among those that drank one can diet soda a day compared to those that didn't drink any.

Interestingly, other studies have found a link between diet soda intake, metabolic syndrome and obesity. For example, the Framingham Heart Study- a huge cardiovascular study based in Framingham, Massachusetts that started in 1948 with 5209 participants and is now on its 3rd generation participants and has taught us most of what we know about heart disease- recently released that they found that people who drank one or more 12-oz soda- diet or regular- had a higher risk of developing metabolic syndrome and of being obese. We know regular soda is associated with increased obesity rates and metabolic syndrome, but why diet soda?

Marion Nesltle points out in her book What to Eat that rates of overweight and obesity have risen in parallel with the increase in use of artificial sweetener. Coincidence? Probably not. Although sweeteners can help some people to reduce caloric intake and therefore, their weight, it seems that most people over-compensate and make up the calories saved, and a lot more!

Another theory, that needs to be researched further, states that because sweetener is very sweet, it signals the body that sugar is coming. Because sweeteners have no calories, we end up craving the calories that were promised but not delivered.

Regardless, the ARIC study results are clear: too much meat, fried foods and diet soda do not add up to a healthy diet or life.