Wednesday, January 25, 2012


Peter Rogers asked me to write a few thoughts on probiotics. He tried a probiotic supplement for three months and didn’t see any benefit. His partner, however, felt an improvement and has stuck with them. You will have seen advertisements for both yogurt with Lactobacillus acidophilis and Bifidobacteria, as well as small bottles of supplemental live bacteria eg Yakult; these are examples of probiotics.

Probiotics is a general term for live bacteria that you consume in a food or as a supplement and which survive the passage all the way through the stomach and the small intestine to arrive safely in the large intestine. Here they settle down and become vigilant against evil forces.

Probiotics = back end health
Having a healthy bacterial balance in the large intestine is linked to normal bowel habits, healthy immunity, improved bioavailability of nutrients and possibly less risk of bowel cancer. With more healthy bacteria in the large intestine means that fewer nasty bacteria are able to get a foothold and cause internal turmoil. For example, the good bacteria like Lactobacillus produce organic acids that retard the growth of nasty bacteria such as Salmonella.

Where probiotics can be very helpful is when you get food poisoning or any condition with diarrhea, because you may have washed out a lot of healthy bacteria too. If you have been prescribed antibiotics then they may kill both the nasty bacteria causing your illness as well as some of the healthy bacteria in your bowel. In both cases taking some probiotics as a supplement or via a food like a yogurt with Lactobacillus bacteria will help re-establish the good bacteria in the bowel and make it difficult for pathogenic bacteria to take a hold. Some people today take probiotics in the precautionary hope it will prevent travelers diarrhea.

Athletes & probiotics
As an athlete’s training load increases so does their risk of illness, such as respiratory tract infections, so anything that has the potential to help the immune system may be able to keep an athlete healthy through heavy training and competition. There have been a few studies on the effects of probiotics and the results have been either positive or neutral.

One study found that a probiotic significantly reduced the severity and duration of respiratory tract illnesses in 20 male elite distance runners (Cox 2010). Another study of male and female athletes found that those taking a probiotic also had a much lower incidence of respiratory tract infections (Gleeson 2011). The authors speculated that this positive outcome might be due to higher levels of immunoglobulin A in those on the probiotic.

Other studies have not seen much difference and a review of all the evidence was not that enthusiastic about taking probiotics, although they did concede that they had potential for athletes undergoing heavy training. These studies are done in elite athletes who are likely to be under greater immune stress and may not have the same benefit for the generally fit and healthy.

The future
There will be more research on probiotics because there is a food industry that can benefit. The future will see more refined knowledge where we will recommend different probiotic bacteria types for different conditions. Whether you have Irritable Bowel Syndrome, food poisoning or have a family history of bowel cancer could determine the type of bacteria you take as a supplement.

What does it all mean?
Remember that for most of human history we never worried about probiotics. I doubt whether anyone mentioned “probiotic” at a dinner party until 1997. If you eat well, keep active, give to charity and overtake safely then there is an excellent chance that the bacteria in your large intestine are in perfect order, doing exactly as they should. In other words, good bacteria are naturally present.

You know your guts better than I do, indeed better than I want to know. So, I’ll leave you to make the decision whether to take probiotics. You might find little benefit like Peter did, or it could add a song to your day as his partner experienced. I’m like Peter. Happy to have yogurt with bacteria, but my resident gut bacteria are doing fine on their own with all that fibre I send their way each day. I don’t think they need “back up”.

Further reading in the Medical Journal of Australia] and the Sydney Morning Herald]

Cox, A.J., et al 2010. British Journal of Sports Medicine 44 (4): 222-226

Gleeson, M., et al. 2011. International Journal of Sports Nutrition and Exercise Metabolism 21 (1): 55-64.


Rod Lees wrote and said: “There seems to be some mixed advice in relation to eggs and cholesterol.” You’re right Rod, and there has been for many years. It was conveniently thought that foods with cholesterol had the potential to raise blood cholesterol. We later realised that it was saturated fat and becoming blobby that made our cholesterol rise. It’s doubtful that it was the omelette you had for brekky.

As with most aspects of our body, genetics has an influence on cholesterol too, meaning you can eat superbly yet require the assistance of medication to get your cholesterol down.

The official word from the Heart Foundation is: Cholesterol in foods has only a small effect on your LDL cholesterol (that’s the nasty cholesterol – Ed), especially when compared with the much greater increase caused by saturated and trans fat in food.

Anyway, eggs are off the hook on the heart disease and blood cholesterol front. The Heart Foundation’s view on eggs is: Eggs are very nutritious. They contain good quality protein, lots of
 vitamins and minerals, and mostly the healthier polyunsaturated fat.

They say that up to six eggs a week is fine. I couldn’t live without my mega-veg frittata with a touch of truffle oil. And if you ever hear about the cholesterol-free egg from the Araucana hen, someone is pulling your leg. All animal foods have cholesterol. That includes you and me. It is part of the cell wall.

More on eggs and nutrition here.

Thursday, January 12, 2012

Novel by Glenn Cardwell

I have written a novel. Why? Look, sometimes my life deviates beyond this nutrition thingy that has gripped me for three decades (+ 10% tax). About three years ago, while I strolled along a deserted beach, a dolphin came into the shallows and made a sign with its tail, which I took to mean “Write an novel young man.” I replied: “I’m not young anymore”, to which the dolphin’s tail semaphored “Well, you better get a wriggle on then sunshine.” 

So here it is. It is available only as a download for your computer or digital reader.

Resistant Starch

You have all heard of fibre, the mainly undigested bits in non-animal foods. You know us nutrition folk worship the stuff because it keeps you and me regular, slows down your eating, slows down digestion and it keeps your intestines healthy. If your bowels are happy, then the whole world seems much more friendly and ordered.

The fibre travels past your stomach and small intestines, and slides into the large intestine teeming with super-helpful and enthusiastic bacteria. These bacteria just love fibre. They will eat fibre all day, reproductively divide with big smiles, while producing compounds that kills bowel cancer cells.
OK, heard all that before; what about resistant starch?
Well, for a long time we thought that fibre was pretty much the only thing in food that did the job of making our waste wholesome, soft and bulky. Now we know that resistant starch (RS) is having a similar effect. It is not really fibre as we know it, although, like fibre, it doesn’t get digested and so the RS ends up in the large intestine. That is, RS is resistant to digestion.

Sometimes RS is called a “prebiotic” because it is used as a food source by the bacteria, much like inulin, a long chain of fructose molecules, which is often added to foods claiming to have “prebiotics”. Inulin occurs naturally in foods like asparagus, garlic, artichokes, bananas, leeks, onions, wheat, barley and rye. Don’t confuse prebiotics with probiotics, a topic I shall chat about in the next edition.

What food has RS?
Foods with high levels of RS include unprocessed whole grains, legumes, green bananas, and cooled, cooked potato (think potato salad). As a banana ripens the (long chain) starch begins to form (short chain) sugars making it sweeter and the RS levels decline. Despite that, about 85% of the remaining banana starch eaten makes it to the appendix where the large intestine begins. That’s why both ends of your digestive system love bananas.

Also, clever folk have been able to selectively breed grains to have a higher RS content. In Australia, you may have seen bread with “High Maize” added; it’s a type of corn with naturally high levels of RS. The “High Maize” starch is added to the bread to increase the fibre content.

Why would starch be resistant to digestion? 
First know this - RS is composed of long chains of glucose. Indeed, that’s what all starches are – very long chains of glucose. Some chains are branched and some are straight. It is the long straight chains that are most likely to resist digestion.

Anyway, here are three common reasons why some starch is RS:

1) Some starch just plain can’t be reached by digestive enzymes during the trip through the intestine; it’s not there long enough for an enzyme to reach it. Happens with whole seeds and wholegrains;

2) the starch is mainly in the form of long straight chains of glucose; enzymes can only break off the end glucose and again they haven’t enough time to get to the middle of the chain eg starch in the banana; and

3) when starch cools after cooking it can form gelatinised starch which outwits the enzymes eg potato salad.

What does it all mean?
Note that all the sources of RS mentioned are whole foods. When a starch gets processed (eg refined flour) it usually takes a beating and starts breaking up. Those long chains become short chains and short chains are dead easy to digest so no starch gets through to the large intestine (which annoys the bacteria there, let me tell you. They really look forward to a feed of RS. Bought something on eBay and not arrive? Times that by 100 and that’s how annoyed they get).

There is much more to the story than I can quickly relate. For example, there are three different types of RS and they are involved in more than just bowel health – they probably help control fluctuations in blood glucose making RS a great diabetes buster.

The message, I believe, is that here is another reason to eat mainly minimally processed foods because they offer bio-active compounds and benefits that you can’t simply replicate by heavily processing natural foods, chucking in some nutrients, then trying to pass it off as close to the original.

If I can put it in music terms: this weekend is the five day Elvis Festival in Parkes, New South Wales where highly processed Elvis impersonators number more than the residents. It is great fun, but for the rest of the year you want to listen the unprocessed original.