Fruits/Vegetables

Sulfites: What Are They And Do They Harm Us?

Sulfites refer to a group of chemical ingredients that are added to processed foods and drinks mainly to serve as a preservative. 

Sulfite-containing ingredients can go by several names, including: 

  • Sulphur dioxide
  • Sodium sulphite
  • Sodium metabisulfite
  • Calcium sulphite
  • Potassium hydrogen sulphite

Sulfites are used to prevent browning/preserve color of foods, bleach flours, increase shelf life of processed foods, and maintain freshness.

Where are sulfites found?

Sulfites are commonly found in the following food and drink products: 

  • Dried fruit
  • Shrimp & processed seafood
  • Soup mixes
  • Jams & jellies (sulfites present in pectin)
  • Baked goods & refrigerated/frozen ready-to-bake dough products (sulfites used as dough conditioner)
  • Canned fruit & vegetables
  • Shredded coconut
  • Molasses
  • Pickled foods
  • Beer & wine
  • Prepackaged citrus juice (those cute little lemon-lime shaped bottles!)
  • Grape juice
  • Gravies
  • Potato products – pre-cut, frozen, and dried, such as instant mashed potatoes
  • Chips

Sulfites are also naturally occurring in some fresh foods, including: 

  • Fermented foods, like sauerkraut and sourdough
  • Grapes
  • Some cheeses, like packaged shredded cheese

Sulfites can even be found in some medications and personal care products! 

Be sure to check ingredient labels and inform your healthcare practitioners and pharmacists if you suspect you’re sensitive or trying to avoid added sulfites.

What is sulfite intolerance – and are sulfites actually bad for you?

Government agencies consider sulfite ingredients as “generally recognized as safe” for human consumption at low concentrations. In most countries, like Canada, Australia, and the US, sulfites are required to be listed on all food and beverage labels. 

True sulfite intolerance is rare and most people don’t experience side effects from consuming food and drink that contains sulfites. But that doesn’t mean it can’t happen! 

The most at-risk population for sulfite intolerance is individuals diagnosed with asthma. It’s estimated that 3-10% of asthma sufferers are also sensitive to sulfite-containing products. 

Those with impaired liver and/or kidney function may also be sensitive to sulfites. That’s because the liver and kidneys normally contain high amounts of sulphite oxidase – the enzyme responsible for converting sulfites to the sulfate form for excretion.

Symptoms related to sulfite intolerance can range from mild to severe and include: 

  • Inflammatory skin reactions, like hives, redness, and swelling
  • Respiratory distress, like wheezing, coughing, and congestion
  • Constricted airflow and/or asthma attack
  • Anaphylactic shock
  • Stomach upset and diarrhea 

If you notice any of the above symptoms following ingestion of sulfite-containing food or drink, you’re likely sensitive to sulfites, and you should consult with your healthcare practitioner for further testing. 

Some studies suggest sulfites can damage or decrease the number of good-for-you bacteria in your small intestine, also known as the gut microbiome. A compromised gut can then lead to many other health issues.

Sulfites in red wine causes headaches, right?

Actually, the jury is still out on what exactly is to blame for the commonly-reported red wine-induced headache. 

Wine contains significantly fewer sulfites compared to other products, such as dried fruit. If you don’t experience a headache after eating dried fruit, it’s unlikely sulfites in wine are causing your headache. 

However, other ingredients in wine, such as histamine and tannins CAN cause headache. Of course, the alcohol itself found in wine may also cause a headache 😉 

If you experience headaches after drinking wine, make sure you’re properly hydrated, or you may just need to avoid wine altogether!

Should I avoid sulfites?

If you or a family member has asthma, you may want to consider removing sulfite-containing products from your home to minimize the risk of adverse reactions. 

If you’re on a mission to improve gut health and/or trying to eat mostly natural foods without added chemicals, you’ll certainly want to avoid sulfite-containing foods. 

The good news is that focusing on a whole foods diet made up of fresh fruits, vegetables, lean proteins, whole grains, and healthy fats automatically eliminates exposure to most sources of sulfites!

(Just another perk your health can benefit from when you cut back on the amount of processed foods in your diet!) 

RECIPE 

Chia Berry Jam 

Ingredients 

2 cups assorted organic berries, such as strawberries, blackberries, or blueberries

3 Tbsp. chia seeds

2 Tbsp. honey

1 Tbsp. fresh squeezed lemon juice 

Preparation 

Place berries in saucepan set over medium-high heat. Cook until berries begin to breakdown and release juices, about 5-10 minutes. 

Remove from heat. Stir in honey, lemon juice, and chia seeds.

Let cool to room temperature. Jam will thicken as it cools. Add 1 tbsp additional chia seeds if you prefer an even thicker jam. Transfer jam to airtight container and store in refrigerator. 

REFERENCES 

Healthline: The 8 Most Common Food Intolerances 

Adverse reactions to the sulphite additives, Gastroenterology and Hepatology from Bed to Bench, 2012.

Considerations for the diagnosis and management of sulphite sensitivity, Gastroenterology and Hepatology from Bed to Bench, 2012. 

Sulfites inhibit the growth of four species of beneficial gut bacteria at concentrations regarded as safe for food, PLOS One, 2017. 

Alcohol and migraine: trigger factor, consumption, mechanisms, Journal of Headache & Pain, 2008.