Sue's Blog

Saccharomyces boulardii and diatomaceous earth - are these failsafe supplements that can help with irritable bowel symptoms?

Earlier this year, we received a report from a failsafer who suffered from severe IB symptoms unless she stuck strictly to a very restricted form of the RPAH diet plus fodmaps. She saw a huge improvement in her symptoms over a 2 month course of:

·         a dietitian-recommended probiotic (Saccharomyces boulardii or SB), plus

·         diatomaceous earth or DE, a silica supplement

Probiotics and silica supplements are not mentioned by RPAH, although many failsafe-friendly dietitians recommend probiotics AFTER the strict elimination diet.

1. Probiotics: Saccharomyces boulardii

Howard and I have been using SB extensively for about four years while travelling overseas and find it really helps to prevent or treat travellers’ diarrhoea. As well, I had noticed that it helps enormously to prevent or treat IB-related bloating and flatulence. When we first started using these probiotics no one had heard of them but now they seem to have become mainstream. We were surprised recently when buying antibiotics for our Nepal medkit that the pharmacist actually recommended taking Saccharomyces boulardii at the same time. There is considerable scientific evidence, see further reading below.


Where to buy

As mentioned in medical journals, we have found the most effective are those that contain the most CFUs (colony forming units)

Our favourite is Travel Bug, available in many pharmacies

The failsafer whose story appears above took a dietitian recommended version, not cheap:

Further reading:

Probiotics: eat your bugs, ABC website

Medical Journal of Australia

A search of Pubmed turns up over 500 scientific references

2. Diatomaceous earth (DE) as a silica supplement, is it failsafe?


This supplement is not mentioned in the RPAH Handbook but it appears to be failsafe and we are hearing from people that it helps.

Obviously, because is not recommended by RPAH, it is not suitable during your strict RPAH elimination diet.

Silica supplements are considered to be very safe because they are inert - but for failsafers it is important to get one with no added flavour or other non-failsafe ingredients.  (Caution: there is an Alkawell product that is definitely NOT failsafe due to the aloe vera juice ingredient that is high in salicylates). We think DE is probably failsafe because it has no added or natural flavour.

Although silica has been used for trials of bone density (it helps for osteoporosis and anything to do with bone and connective tissue problems), it hasn't been trialled for irritable bowel - but everyone says the first thing it does is to establish bowel regularity whether you suffer from irritable bowel symptoms with predominantly constipation or diarrhoea.

Travellers’ diarrhoea

Our 2015 trip to Nepal involved 40 days trekking along the Tibetan border in the remotest region on the planet. It was the toughest trip we've ever done and I managed without any travellers’ diarrhoea. I was taking 2 Travel Bug and 1 tsp of DE every day; by the end of the trip we were running low on Travel Bug so Howard was taking one Travel Bug a day and no DE and on the last day of the trek he came down with a nasty bug (that I managed to avoid) for which he had to take antibiotics. My opinion is that the DE helped with that too and I am usually the one who has the problems.

How to take

It is usually recommended to take DE in water, milk, juice or tea. Obviously to be failsafe, forget the juice or tea. I have found the most palatable way for me to take it is in water, decaf coffee or a carob drink (carob powder with water and/or soymilk). Most people start with one teaspoon per day and work their way up to one tablespoon per day (NOTE: you have to expect a cleanout in the first couple of days).

If you decide to use it I would be very interested to hear what you think of it. Please understand that this is NOT a recommended part of the RPAH diet and it should NOT be used with the RPAH diet. Some people may like to try after they have finished a dietitian-supervised trial of the RPAH elimination diet. 

More information about Food Grade DE (Diatomaceous Earth)

Health Benefits of Diatomaceous Earth by Dee McCaffrey, CDC   (formerly an analytical chemist for 19 years, now a nutritionist)

"You’ve probably never heard of one of the best and most economical supplements to improve your health and cleanse your body. In fact, this supplement is perhaps one of the best kept secrets ever. This relatively unknown “food” supplement is called Diatomaceous Earth, also known as DE. It is a completely natural substance that is rich in naturally occurring silica, a mineral whose list of documented health benefits continues to grow as more research is being conducted ....". See the rest of the article and watch the video at

Where to buy

Unflavoured food grade DE (we get the superfine grade, the first one) available in Australia from

Further reading: the Science

While silica has been used for trials of bone density (it helps for osteoporosis, anything to do with bone and connective tissue problems), it hasn't been trialled for irritable bowel -  but everyone says the first thing it does is to establish bowel regularity.

Silicon: A Review of Its Potential Role in the Prevention and Treatment of Postmenopausal Osteoporosis. Charles T. Price, Kenneth J. Koval, and Joshua R. Langford Int J Endocrinol. 2013

Abstract: Physicians are aware of the benefits of calcium and vitamin D supplementation. However, additional nutritional components may also be important for bone health. There is a growing body of the scientific literature which recognizes that silicon plays an essential role in bone formation and maintenance. Silicon improves bone matrix quality and facilitates bone mineralization. Increased intake of bioavailable silicon has been associated with increased bone mineral density. Silicon supplementation in animals and humans has been shown to increase bone mineral density and improve bone strength. Dietary sources of bioavailable silicon include whole grains, cereals, beer, and some vegetables such as green beans. Silicon in the form of silica, or silicon dioxide (SiO2), is a common food additive but has limited intestinal absorption. More attention to this important mineral by the academic community may lead to improved nutrition, dietary supplements, and better understanding of the role of silicon in the management of postmenopausal osteoporosis.

See full text with references of many other silica supplement studies at