Sulfites: Evil or Tolerable?

After our recent discussions about natural vs. organic vs. biodynamic wines, I became more intrigued about the complexities of these classifications both in the US and in Europe. Interestingly, the popularity of the term "organic" or "natural" has led to a the growth of a new market related to the wine industry: products which allow for non-sulfite winemaking. For several reasons, there has always been a strong association between sulfite concentration and natural/organic/biodynamic wines. In response to rising demand for no or low sulfites, specific yeasts such as Primaflora, tannin products derived from grape pips, and "enzyme soups," among other things, have now entered the market. Alice Feiring, who is a big proponent of natural winemaking, argues that it is possible to make good wines without using an these additives to replace SO2. I do think it is quite challenging, however, especially in particular regions and for particular varietals. A link to her discussion here: http://www.alicefeiring.com/blog/2015/12/2016-wine-trend.html.

Should wine be low-sulfite, or sulfite free? And if so, what should the cutoff be? Although different answers have been postulated, these questions have not been thoroughly researched and there remains a fair amount of uncertainty about sulfites in wine. First, the prevalence of true sulfite sensitivity or allergy in the population is quite low, and is most frequently associated with asthmatics. What about the association of sulfite with headaches? The Journal of Head and Face Pain published an article in 2014 which describes a potential link between phenolic flavonoid radicals and headache. However, regarding sulfites, it states:

"Sulfites were once linked to headache after wine ingestion. However, most of this belief is either speculative or in fact wrong, since the food and wine preservative sulfur dioxide (SO2), called generically sulfite, although present in wines, is much more existent in common foods that do not trigger headache attacks, such as dried fruit. While red wines contain around 160 parts per million (ppm) of sulfites, white wines reach 210 ppm and dried fruit up to 1000 ppm. Moreover, recently produced organic wines contain lower levels of sulfites or, indeed, have none at all, but the persistence of the headache triggering potential remains. In addition, published literature has not yet established any links between the presence of sulfite and headache." (http://onlinelibrary.wiley.com/doi/10.1111/head.12365/full)

Although there is quite a bit of interest in low sulfite or no sulfite wines, and although I do think that high sulfite concentrations can affect taste and may lead to over-ingestion, I do think it will be important to have a clearer understanding of what the risk and benefits are in order to determine - especially at these lower concentrations - whether it really makes a difference, and whether it is really worth using these new additives on the market as a substitute.