Y.A.C.S. Diet Information

Y.A.C.S. stands for Yeast, Alcohol and Chemical Sensitivity. It is a diet and also a lifestyle in that it involves choosing particular personal care products and avoiding particular high chemical exposure activities.

This page features a list of ‘allowed’ and ‘banned’ foods. Of course you are in control of what you eat or don’t eat so nothing is really ‘banned’, however this list should make it clear what you can and cannot eat to be on the Y.A.C.S. diet.

*Please note, many people with a yeast sensitivity may have yeast naturally growing in their gut. This yeast will be fed by carboyhdrates and therefore you may find after consuming carboyhdrates you feel lethargic or ill in other ways. If this is the case for you, you may wish to stick to low or moderate-low carbohydrate recipes.

Food to avoid

  • Yeast – this includes risen bread (including pittas which are risen with yeast)
  • Yeast extract- common ingredient in many supermarket foods
  • Citric acid – produced by fermentation process using yeast
  • Vinegars (including vinegars considered healthy such as apple cider vinegar, and including distilled vinegar, also including foods where vinegar is a contained ingredient such as mayonnaise or tomato ketchup)
  • Alcohol – specifically Ethanol, the type of alcohol found in alcoholic beverages
  • Alcohol free beer or wine – i.e. things that did contain alcohol but the alcohol was removed
  • Vanilla essence – this diet avoids alcohol and you may be surprised to learn that only a moderate proportion of vanilla essence alcohol evaporates during baking
  • Bananas – these contain low levels of alcohol
  • Fruit juices (unless freshly squeezed, these undergo fermentation)
  • Oranges – contain a naturally occurring chemical that may cause sensitivity
  • Peppermint & Spearmint – contain a naturally occurring chemical that may cause sensitivity
  • Sweeteners (including Stevia)
  • Flavourings – this word means almost anything could be an ingredient
  • Malt products
  • Vegetable oils such as rape, sunflower and olive oil. (Olive oil might have been fine however both organic and non-organic have been found to contain high levels of pesticides and herbicides). Avocado oil should be fine.
  • Nitrates (found in most bacon)
  • Sulphites (found in most sausages and bacon)
  • Carbonic acid (found in sparkling water and fizzy drinks)
  • Unfiltered tap water
  • Fermented soya or other fermented products
  • Tofu
  • Burnt food
  • Smoked foods such as smoked salmon, smoked paprika, and chipotle
  • Cheeses especially strong or moldy cheeses. You may find you can tolerate mild cheddar, cream cheese or cottage cheese, however the recipes on this site will avoid all cheeses
  • Black pepper

Household and personal care products to avoid

  • Regular toothpaste containing fluoride and huge numbers of other chemicals
  • Teeth whiteners containing sodium peroxide (bleach)
  • For toothpaste, soap and shower gel, avoid almost all chemical ingredients except for those which you can be reasonably sure you aren’t sensitive to such as bar soap ingredients like Sodium Olivate)
  • Products containing Parfum
  • Products containing Sodium Benzoate (this is very common and it is also a permitted organic ingredient)
  • Strong bleach cleaning products such as mold killer

Other things to avoid

  • Strong diesel/petrol fumes
  • Interior and exterior household paints – until dry and left for e.g. 24 hours
  • Soft plastics that smell of plasticizers

Allowed food

  • Organic fruit and vegetables excluding those on the ‘Foods to avoid list’
  • Lemon/ lime juice as a substitute for vinegar
  • Un-enriched flours such as stone-ground organic flour
  • Milk, butter & cream (unless you have a dairy intolerance)
  • Powdered vanilla
  • Organic chamomile tea, ginger tea (most herbal teas other than mint, watch out for flavourings)
  • Black or Green Tea and coffee only in moderation (suggested 2 cups per day, these are products of fermentation)
  • Spices and herbs, aim for organic where possible, with the exception of black pepper which should be avoided
  • Organic coconut oil
  • Coconut milk (check the ingredients and aim for pure coconut milk)
  • Organic meat & fish and derived products such as lard/dripping
  • Bacon and sausages free from nitrates and sulphites such as Naked Bacon, but ideally organic
  • Organic grains, nuts and seeds
  • Filtered, boiled or bottled still water
  • Baking powder & Bicarbonate of soda
  • Honey and sugar* (see note above on carboyhdrates)
  • Guar gum – a common additive that seems to be harmless
  • Yeast free bread – wraps such as piadina flatbreads (watch out for citric acid in most tortillas)