When they add nothing, as lambic-makers do, the untreated wort becomes a refuge for airborne wild microflora, which now have space to grow and food that would otherwise be hogged by beer yeast to eat.

WSJ: The Sour and the Glory of Beer

In some cases, certain foods, such as cow's milk, eggs, fish, shellfish, yeast products, nuts, and some food colourings and preservatives, can make symptoms worse.

BBC: Fast-food 'linked to childhood asthma and eczema'

Last year, the U.S. Food and Drug Administration banned the imports of red yeast rice from China, saying it was a drug and not a supplement.

CNN: Studies: Chemical in some Chinese cuisine can lower cholesterol

Guarente's yeast lived longer when they were given less food, and the underlying mechanism seemed to be that starvation tripped SIR2.

FORBES: Starvation--And Long Life--In A Pill?

For instance, Unilever scientists have spent five years working with yeast cells that replicate human taste receptors, and then extracting substances from food to see how they might trigger these receptors.

FORBES: On The Cover/Top Stories

Ingredients that hold moisture, including autolyzed yeast extract, sodium phosphate, and soy protein concentrate, further soften the food.

NPR: Excerpt: 'The End Of Overeating