Back in 2007, after a series of mostly ineffective treatments prescribed by doctors, Ms. Enders, then 17, decided to take matters into her own hands. Convinced that the illness was somehow associated with her intestines, she pored over gastroenterological research, consumed probiotic bacterial cultures meant to aid digestion and tried out mineral supplements.

The experiments worked (although she is not sure which one did the trick), leaving her with healthy skin and a newfound interest in her intestines. “I experienced with my own body that knowledge is power,” she writes of the episode in “Gut: The Inside Story of Our Body’s Most Underrated Organ,” which was published in North America last month after its surprising success in Germany, where it has sold almost 1.5 million copies since its release in March 2014.

Solar water disinfection

Water can be disinfected and in this way made drinkable using the rays of the sun. “Solar water disinfection” – SODIS for short – thus offers a solution for preventing diarrhoea, one of the most common causes of death among people in developing countries.

Clean drinking water in 6 hours

The SODIS method is ideal for treating water for drinking in developing countries. All it requires is sunlight and PET bottles. How does it work? Clear PET bottles are filled with the water and set out in the sun for 6 hours. The UV-A rays in sunlight kill germs such as viruses, bacteria and parasites (giardia and cryptosporidia). The method also works when air and water temperatures are low.

People can use the SODIS method to treat their drinking water themselves. The method is very simple and its application is safe. It is particularly suitable for treating relatively small quantities of drinking water.


Many scientific studies confirmed the effectiveness of the SODIS method. It kills germs in water very efficiently. The method has even been shown to improve the health of the population. Research into training strategies gave insight about which communication methods are most suitable. It has also been proven that the use of PET bottles in the SODIS method is harmless.

Solar water disinfection is a type of portable water purification that uses solar energy to make biologically-contaminated (e.g. bacteria, viruses, protozoa and worms) water safe to drink. Water contaminated with non-biological agents such as toxic chemicals or heavy metals require additional steps to make the water safe to drink.

There are three primary subsets of solar water disinfection:

  1. Electric. Solar disinfection using the effects of electricity generated by photovoltaic panels (solar PV).
  2. Heat. Solar thermal water disinfection.
  3. UV. Solar ultraviolet water disinfection.

Solar disinfection using the effects of electricity generated by photovoltaics typically uses an electric current to deliver electrolytic processes which disinfect water, for example by generating oxidative free radicals which kill pathogens by damaging their chemical structure. A second approach uses stored solar electricity from a battery, and operates at night or at low light levels to power an ultraviolet lamp to perform secondary solar ultraviolet water disinfection.

Solar thermal water disinfection uses heat from the sun to heat water to 70-100 °C for a short period of time. A number of approaches exist here. Solar heat collectors can have lenses in front of them, or use reflectors. They may also use varying levels of insulation or glazing. In addition, some solar thermal water disinfection processes are batch-based, while others (through-flow solar thermal disinfection) operate almost continuously while the sun shines. Water heated to temperatures below 100 °C is generally referred to as Pasteurized water.

High energy ultraviolet radiation from the sun can also be used to kill pathogens in water. The SODIS method uses a combination of UV light and increased temperature (solar thermal) for disinfecting water using only sunlight and plastic PET bottles. SODIS is a free and effective method for decentralized water treatment, usually applied at the household level and is recommended by the World Health Organization as a viable method for household water treatment and safe storage.[1] SODIS is already applied in numerous developing countries. Educational pamphlets on the method are available in many languages,[2] each equivalent to the English-language version.[3]


Traditionally, kvass is made from stale, sourdough-rye bread. This produces a drink with a taste similar to beer—minus the alcohol content—and with all the health properties listed above. But for those of us who have been forced, by allergies or auto-immune diseases, to eliminate grains from our diet, all is not lost. While rye-bread kvass is certainly the most well known, it is not the only variety available to us. Indeed, Russians have been known to create kvass with all manner of ingredients: from currants and raspberries to lemons and cherries. The most common and perhaps most beneficial alternative, however, is beets.

LifeStraw personal water filter

Published on Jan 7, 2014
Krik of Black Owl Outdoors shows you the LifeStraw personal water filter. Light, compact and inexpensive; the LifeStraw is perfect for camping, hiking, and backpacking.

Published on Jun 5, 2013
See the LIFESAVER bottle in action with Michael Pritchard, drinking directly from the river on the move!

Gravity-Driven Membrane (GDM) technology

Inadequate access to microbiologically safe drinking water continuously threatens the health and well-being of more than a billion people, primarily in developing countries. In many areas worldwide the central water infrastructure is not available at all, or not reliable, leading to unsafe water at the tap. In such cases, decentralized water treatment can be used.

Ultrafiltration is an effective technology to treat water and in principle can be applied on a decentralized scale. Most ultrafiltration membranes have pores which are smaller than the size of bacteria and viruses. Thus, water filtered through these membranes is microbiologically safe.

During dead-end ultrafiltrtion all macro- and microorganisms, particles and colloids accumulate on the membrne surface and a fouling layer is formed. Backflushing or chemical cleaning are usually used during conventional ultrafiltration to remove fouling layer. This prevents the membrane from clogging, which is expected to occur during filtration on a long term. However, backflushing or cleaning results in complex and maintenance-intensive systems, which are difficult to operate on a long term in developing countries.

reliable information about nutrition

Valuable additional resources that contain reliable information about nutrition are available at the British Nutrition FoundationMedline PlusHarvard Nutrition Source and For advanced students, the use of Pubmed is recommended. Pubmed is a public database for the scientific literature in the fields of biomedicine and health that also covers portions of the life sciences, behavioral sciences, chemical sciences and bioengineering. PubMed is a free resource that is developed and maintained by the National Center for Biotechnology Information (NCBI) at the U.S. National Library of Medicine (NLM), located at the National Institute of Health (NIH). When using PubMed and other databases, the inclusion of search terms such as “review” and “meta-analysis” is recommended. These are the terms used for certain types of articles that provide a broad overview of a topic. For instance, if you are interested in overview articles about the relation between dietary fiber and colon cancer, enter the search terms “colon cancer” (or “colorectal cancer”), “dietary fiber” (or “dietary fibre”) and “meta-analysis” or “review” using the advanced search tool in PubMed.

Information about the nutrient content of foods is available from the USDA and through Eurofir. Many countries have their own website that provides information on food composition. The website used in the Netherlands can be found here.