Chat with Vinny

What you need to know about sulphites in wine – Laithwaites

Everything you need to know about sulphites in wine

Posted on April 9, 2025 by Louise Springham

Looking to find out more about sulphites in wine? You’re in the right place. Our handy guide will tell you everything you need to know – from what they are to why they’re used. Read on to learn more …

The practice of adding sulphites to a wine before bottling sparks ongoing debate in the wine world. Some winemakers believe they’re vital for preserving wine, while others refuse to handle them at all.

But what are sulphites exactly? Friend or foe? The culprits behind those pesky wine headaches? Let’s take a closer look ...

What are sulphites?

Sulphites (also known as sulphur dioxide or SO₂) are a group of chemical compounds found in many foods and drinks, including wine where they act as an antimicrobial – helping to prevent spoilage and oxidation.

Even if a winemaker adds no sulphites, they are still present in wine due to the fermentation process. Yeast naturally produces small amounts of sulfur dioxide while converting sugar into alcohol, meaning that all wines contain sulphites to some degree. The levels vary depending on grape variety, fermentation conditions, and winemaking choices.

Sulphites have been used in winemaking for centuries. The Romans discovered that burning sulfur candles inside wine amphorae helped preserve freshness. By the 18th century, the practice of adding sulphites to wine was widely adopted.

Fast-forward to today and winemakers carefully control sulphite levels, using just enough to protect the wine while keeping its flavour and balance in check.

A row of vines with a person hand-harvesting

Are sulphites bad for you?

For most people, sulphites are not bad and are generally considered safe. But a small percentage of the population, especially those with asthma, may experience sensitivities or reactions. If this sounds like you, keep reading to find out more about naturally low-sulphite wines.

Also, there’s no evidence that sulphites cause headaches. In fact, if you really want to banish those nasty wine headaches, it's histamines you need to watch out for. These are a naturally occurring compound found in grape skins, especially red grapes. If you’re particularly susceptible to headaches after a night on the wine, maybe consider white wine options.

It's worth noting that while hydration doesn't directly combat or "flush out" histamines, it can help mitigate the effects of dehydration such as wine headaches. So, if you love yourself a glass of red wine, ensure you drink plenty of water alongside it.

The role of sulphites in wine production

Sulphites play a crucial role in maintaining a wine’s freshness and flavour. They help prevent the wine from bacterial growth and slow down chemical reactions that could lead to faults.

Wine is also quite susceptible to oxidation, which can dull its flavours and aromas. Sulphites act as a natural shield, protecting wine from excessive oxygen exposure, keeping it vibrant and enjoyable.

Wine also often travels long distances before reaching your glass. Temperature changes, movement, and time in transit can all affect its stability. Sulphites help wines withstand these conditions by preserving their structure, preventing premature ageing and ensuring they arrive in perfect condition.

A group of friends sitting around a table in a vineyard enjoying white wine

How to minimise your intake of sulphites

Certain wines naturally require fewer sulphites. Look for red wines (which contain natural antioxidants and need less SO₂) and wines from small producers who often use minimal intervention techniques. Fresh, early drinking styles typically have lower sulfite levels than long-aged wines.

In the UK and EU, any wine containing more than 10mg of sulphites must state "Contains Sulphites” on the label. However, this doesn’t indicate the exact amount. Some wines may include phrases such as “low sulfite” or “no added sulphites”, which suggest minimal or no additional SO₂ beyond what’s naturally produced.

Organic wines have stricter sulfite limits than conventional wines, while biodynamic wines follow similar principles. Natural wines often have little to no added SO₂, though this can mean they’re more sensitive to storage conditions. If you’re looking to cut down on sulphites, these options are a great place to start.

The bottom line on sulphites in wine

In short, sulphites are essential in winemaking, preserving freshness, preventing spoilage and ensuring stability. While some people worry about their effects, only a small percentage of the population is truly sensitive to sulphites. For most wine drinkers, the benefits far outweigh any risks.

If you experience reactions like headaches or congestion, it’s worth noting that sulphites are more common in white wines, sweet wines, and sparkling wines than in reds. Opting for low-sulphite, organic, or natural wines may help, but other factors like histamines and tannins also play a role.

However, for most, enjoying wine in moderation and staying hydrated is the best way to avoid unwanted effects.

Chablis wine being poured

About the author

Louise Springham

Louise’s first copywriting experience was for a small pet start up in Paris during her time at university … fast forward 5 years and she’s switched cats for clarets. Whether it’s getting stuck into an SEO blog, crafting a pithy headline or studying for a WSET exam – she’s Level 2 qualified in both Wine and Spirits – it’s safe to say she adores it all. You’ll often find her chatting to anyone who’ll listen about her love for oaky Californian Chardonnay (she’s working hard to eliminate the dreaded ‘ABC’ mantra) or reminiscing about summers past in Provence.