Are You Sensitive?

Are you sensitive? I don’t mean to get too personal; but, if you are not sensitive to sulfites, there isn’t much reason for reading the rest of this story. I am quite sensitive, lucky me. When I was younger, I had lots of headaches but just thought I was prone to tension. When I was in college and got drunk with the other guys, I just thought everyone had hangovers that lasted all day. As I got older and the headaches became more frequent, I started looking for a cause and perhaps even a cure. Now in those days, I listened to a lot of talk radio and got some ideas about chocolates, then caffeine and finally aspartame. But nothing really panned out until I heard about sulfites. Slowly, the light began to turn on. And, as I learned more about which foods were likely to contain high levels of sulfites, things became clear. At least to me. Apparently, my wife was not as convinced as I was. So, one day she purposely slipped a known sulfite into dinner. Of course, I got a headache and we both puzzled over what had caused it. Now, my wife is a pretty smart lady; so, she didn’t admit her dark deed until months later when it was easy for me to forgive her. To the cold-blooded scientist, this is equivalent to a blind test. Maybe I should actually thank her…no, I don’t think so.

ChemistAs I mentioned in the last chapter, sulfur preservatives can be dissolved as ions or bound to organic molecules and the human body reacts similarly, but not identically, to all forms. To sort this out, I used by own body as a test apparatus. I prepared a calibrated solution of sodium sulfite in water and drank it, carefully avoiding the concentration that would turn Dr. Jeckle into Mr. Hyde. About twelve hours after drinking 100 micrograms (abbreviated 100 ug) of SO2 in the form of sodium sulfite, I develop significant pressure around my forehead and behind my eyes. If the dosage is increased to 130 ug, a moderate headache develops. By taking controlled amounts of the more commonly sulfited foods and noting my reactions, I was able to document the headache potential of sulfur additives. For instance, if a certain amount of corn syrup gives me a moderate headache, I assign that amount of syrup an SOx value of 130 ug. The SOx concentration of the syrup is then 130 ug divided by the weight of the syrup that I ate. Presumably, the headache is a measure of the swelling caused by sulfites and sulfur dioxide, which should apply to asthma and other responses as well.

I am not quite a mad scientist, but my kitchen skills end at the microwave. So, my attempts at food experiments may not be exactly commonplace and may even seem silly to an experienced chef. What the heck; you live and learn.

Comedy aside, experiments with sulfur additives did allow me to assign useful numbers to all of the ingredients you will encounter on food labels. And, they point out very interesting time relationships. A strong dose of a dissolved sulfite like sodium bisulfite starts causing trouble about 6 hours after ingestion and can father a headache that lasts for more than a day. A mild dose takes 12 hours to cause a problem, as does a sugar like corn syrup. A caramelized sugar, like caramel color, produces trouble after a delay of 18 hours. And starches and eggs, which are more difficult to digest, require 24 hours to cause a headache. These are my times; allergic responses would be much more rapid, perhaps a matter of minutes.

A quick way to determine sensitivity to sulfites is to think back over your response to common foods. Whether you are allergic or sensitive, a sulfite response generally involves the swelling of body tissue. The swelling causes difficulties exhaling if you are asthmatic, headaches if you are like me, or other problems that might be aggravated by swollen tissue. Listed below are some common foods along with average serving sizes, rough delay times and typical levels of effective sulfur oxide (SOx). The delay times are the delays I experience before a mild headache actually develops. Your personal delays might be shorter but would probably follow a similar pattern. By comparing your eating habits and problems with this list, you may estimate your tolerance. Note that white wine usually contains more oxides of sulfur than red wine, although red wine seems to have more of a reputation for hangovers. This is because red wine contains histamines that can also cause problems. And, the alcohol in any wine can cause migraines, so you see how complicated things get. If you are sensitive to sulfites, you will have a problem with large servings of all of the foods in this table, not just one or two. In my case, the effects are cumulative over a 24 hour period.

Common Foods Table

Group Common Foods Serving Delay (hr) SOx (ug)
Breakfast Hash Brown Potatoes 1 dish 24 hours 560 ug
  Toast with Grape Jelly 2 slices 12 250
  Pancakes with Syrup 1 stack 12 240
  Lowfat Yogurt 8 ounces 24 200
Lunch French Fries 1 lg bag 24 2275
  Chocolate Shake 1 lg shake 12 480
  Super-size Cola 22 ounces 18 320
Salad Fat Free Salad Dressing 2 tablespn 12 150
  Wine Salad Dressing 2 tablespn 12 400
  Lemon Juice Concentrate 1 teaspoon 12 770
Dinner Inexpensive White Wine 1 wine glass 12 7500
  Quality Red Wine 1 wine glass 12 3000
  Instant Potatoes 2 scoops 18 2100
  Pizza 4 slices 12 1600
  Canned Potato Soup 1 cup 18 420
Snack Dried Fruit 4 pieces 12 3500
  Gummy Worms 5 worms 18 210
  Candy (jelly beans) 26 pieces 12 160

The Common Foods Table presents typical levels of effective sulfur oxide for most foods. The actual levels may vary from brand to brand and from year to year. However, a few of the simpler ingredients are quite consistent and may be used to gauge your tolerance more accurately. One such ingredient is bottled lemon juice concentrate. Most of the bottles actually carry the concentration on the label. A very typical concentration is 1/40 of 1% which works out to the value listed in the table. For instance, if teaspoon of lemon juice concentrate is no problem but 1 teaspoon causes you trouble, your threshold would be somewhere between 385 and 770 micrograms. If this were the case, you should limit your consumption of SOx to 385 micrograms per day.

Since oxides of sulfur are in so many foods, sorting out your sensitivity from your recollection of what you have eaten may only give you a general idea of your tolerance. And, since some additives don’t cause problems for 24 hours, it is very easy to get confused and come to false conclusions. Like me, you may be tempted to experiment with your sensitivity to sulfites by eating foods not normally on your diet. Please make no mistake…I do not recommend such experiments. Sulfite experiments can be dangerous. I recommend only that you monitor your normal eating habits.


If you cannot accurately determine your sensitivity to sulfites by just recalling what you have eaten recently, perhaps a food diary will help. Just write down everything you eat and note the date and time. Also, record any health problems that occur over the same period. Now, I know it’s a pain to write everything down but you might learn something valuable about yourself. Monitor your diet for at least one week. Then, look over your notes and try to discern a pattern. Of course you will find that you eat too many calories, too much fat, too little fiber and way too much salt. But don’t worry about any of that. Just look for sulfur preservatives.

Perhaps now would be a good time to describe my bottle of sodium sulfite. I use it to make standard sulfite solutions to calibrate my headache response. The bottle is about the size of a fat glass of milk and holds 454 grams of pure sodium sulfite. This is enough to give me a mild headache every day for 5,683 years. That’s not a misprint. That’s five thousand years, probably longer than civilization is going to last. Perhaps I bought too large a bottle. Actually, I don’t handle the bottle directly. I usually get my son to mix up a less lethal solution while I leave the house. It’s not that he is so brave. It’s not that he is so stupid. It’s just that he is not sensitive to sulfites…yet.

If you have a technical background, you may be bothered by my use of grams as a weight. Strictly speaking, a gram is a unit of mass, which takes on the character of a force or weight in a gravitational field. I think weights are more appropriate for the kitchen, where pinches of salt can make or break a meal. By the way, is a pinch a force or a mass?

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