Tuesday, September 29, 2009

When is a sweetener artificial?

Artificial sweeteners have been around a very long time. The first sweetener that wasn’t related to sugar or honey was created in 1878 (131 years ago). It was called saccharin. It became a sugar substitute during the sugar restrictions of WWI and WWII, later to become part of the new “dieters” drinks of the 1960s.

Sweeteners have been associated with cancer since massive amounts of saccharin given to rats caused bladder cancer. How much saccharin? About 3000 times the amount any human was likely to consume. This research has now been dismissed and in May 2000 saccharin was removed from the list of potential carcinogens.

The small, sweet protein

The most common sweetener, aspartame, was discovered in 1965 and was approved for use in food in 1983 in the US and 1985 in Australia. You will find aspartame in low joule or low sugar products that are kept cool, such as soft drinks and yogurt.

Aspartame is not really artificial because it is made of two amino acids (phenylalanine and aspartic acid), both of which are found in any food with protein, from bread to beef. And that is why it is only found in cool foods – once you heat it, being a small protein it will lose its original structure and no longer be sweet.

It is the most researched and evaluated food additive in the world, yet many have been active against its use. A lot of fuss over a small protein, or more accurately, a peptide.

No cancer risk found

The cancer-sweetener association is still prevalent. Recently, Italian researchers took a look at sweeteners and the risk of getting cancer of the stomach, pancreas and endometrium. Over 1000 cancer patients were matched with over 2000 controls to see if there was a link between sweetener use and cancer risk. The researchers concluded: “….. the present study adds further evidence on the absence of an association between low-calorie sweetener (including aspartame) consumption and the risk of common neoplasms ..…”

This is not the first paper to absolve sweeteners of cancer blame. Many other cancers have been assessed and were not associated with sweeteners. In 2006 a US study of 285,000 men and 189,000 women found no link between aspartame and leukaemia, lymphomas or brain tumours.

What does it all mean?

The evidence won’t quell the fear mongers. Occasional consumption of aspartame is very unlikely to be a health concern. Even the high end users consume well below the Acceptable Daily Intake for aspartame determined internationally by food scientists. No, food scientists don’t conspire to harm the public. They, in fact, set very high safety margins for sweeteners and other additives such that even the crazy folk who drink two litres of diet soft drink a day won’t be harmed by a sweetener (however, their tooth enamel is likely to be eroded by the acid in soft drinks).


Cancer Epidemiology Biomarkers & Prevention 2009; 18 (8): 2235-2238

Cancer Epidemiology Biomarkers & Prevention 2006; 15: 1654-1659

Wednesday, September 16, 2009

Fruit hoaxes

Here is a law that hasn’t been broken since the internet started: Health warnings about food received via email will be a hoax. Yes, that includes those about margarine, Diet Coke, artificial sweeteners, and even the very positive one about bananas.

A recent one proclaimed that fruit should only be eaten on an empty stomach, and never after a meal. A quote from this ludicrous email: “Let’s say you eat two slices of bread and then a slice of fruit. The slice of fruit is ready to go straight through the stomach into the intestines, but is prevented from doing so. In the meantime the whole meal rots and ferments and turns to acid”.

So, let me get this right – when I eat a banana sandwich, the bread races to the pyloric sphincter (where the stomach joins the small intestine) and road blocks the banana from traveling any further? The banana then looks forlorn because it is locked in the stomach and decides to ferment to pass the time.

Embarrassingly out-of-date

This notion would have had some credibility in the 18th century. Then, along came a bloke called William Beaumont who did a range of experiments in the 1820s on another human being called Alexis St Martin. Later Beaumont published a book in 1833 called Experiments and Observations on the Gastric Juice and the Physiology of Digestion detailing how he proved that all mixes of food was digested. Nothing rotted or fermented. Every physiology book in the 176 years since has agreed with Beaumont.

You can eat fruit any time of the day, seated or standing, in any season of the year, and in either hemisphere. Gets digested the same. Whenever you read a claim that food rots, putrefies or ferments in your guts, it is just someone going public about not having a clue about basic biology. And that is their right in a democracy. Sadly.

The fruit salad tree

Harry Tomlinson, by all accounts a good and honest bloke, awoke to find that his apple tree was now growing plums and blackberries. The tree in his garden in northern Wales had been growing apples for 30 years before other fruit appeared. He got some publicity back in 2005, with at least one journo asking a horticulturist for an explanation for the “fruit salad” tree. Then someone did the smart and obvious thing. They looked at the tree. You see, Harry was 94 years old, and his sight may not be the best. He was informed by a visiting horticulturist that the maverick fruit had been pasted on the apple tree. Harry wasn’t too pleased. “I think it’s a rotten trick” he told the BBC.

What does it all mean?

It means that some people enjoy fooling others. You have heard the old pearler about only being able to eat fruit before 12 noon. That came from Harvey and Marilyn Diamond, written in their silly book Fit for Life.

I always ask the question “Would this sound logical in a hunter-gatherer lifestyle?” In other words, does it make sense if we consider how people lived 5000 years ago? How would anyone know it is 12 noon five thousand years ago? If a protein meal offered itself early one morning, would it make sense to tell your neighbour “Leave the fish be Joe, it’s way too early to eat protein.”

The digestive tract is very clever. The body is designed to digest all types of food at any time because that made it so much easier for humans to survive.

Does organic food have more nutrients Pt2?

In my last newsletter I mentioned a report that, simply put, said that conventionally grown produce and organically grown produce had similar nutrient profiles. Just as the dust was settling on the conventional vs organic debate, another report, published in Agronomy for Sustainable Development this month, made a case for organic produce.

The new report states that organically grown fruit and vegetables tend to have higher levels of antioxidants, which may benefit human health. There is a logic here, as the antioxidants in plants are often working as nature’s natural pesticides helping the plant keep bugs at bay. If pesticides are not used by the farmer then organic fruit and vegetables have to produce more of their own version to make them less attractive to bugs.

The report also said that the mineral content did not differ between production systems, although there appeared to be higher levels of iron and magnesium in some organically grown vegetables.

Organic produce consumption is on the rise in western societies. As I mentioned in the last newsletter, if you can afford organic then support the movement. We are lucky to have the choice.

You can download the original paper here: http://www.organicconsumers.org/artman2/uploads/1/ASD_Lairon_2009.pdf

References: Agron Sustain Dev 2009; doi 10.1051/agro/2009019