7 arginine-rich foods to avoid if you're prone to cold sores

Diet and cold sores

As with most health complaints, diet is an important factor for preventing cold sore outbreaks. A generally poor diet that lacks fruits, vegetables and complex carbohydrates, instead focusing on trans fats, sugar and meat, will weaken your immune system, leaving you vulnerable to an outbreak.

However, many of the foods that people turn to when looking to improve their diet are actually rich sources of arginine – a usually useful amino acid, but one that is thought to trigger cold sores in a lot of people.

Most people find that they can still enjoy the following foods within moderation, but if you’re experiencing frequent recurring outbreaks, then diet is something you should definitely look at and I’d recommend cutting out the following foods on a trial basis to see if it helps.

7 arginine-rich foods to avoid

1. Nuts

These are the worst offenders! While nuts are usually a great way to get healthy protein, fibre and minerals, they are also a high source of arginine.

In particular, peanuts, walnuts and hazelnuts are the worst offenders so steer clear of these. This includes peanut butter and other nut butters unfortunately!

2. Pumpkin Seeds

Another super healthy but unfortunately high-arginine food is pumpkin seeds. You might also want to avoid sesame seeds as these are packed full of arginine too.

3. Chocolate

Chocolate is a rich source of arginine, and though we’re often told that darker chocolate is better for us, this may not be true in this case as darker chocolate tends to have more arginine.  

4. Spirulina

This super healthy green super powder might not be so super for people who often get cold sores! This blue-green algae is typically added to smoothies and protein shakes for extra nutrition, but it’s also quite high in arginine. 

5. Squash

Squash might be your go-to winter veg, but it is actually a fairly rich source of arginine so may be best avoided!

6. Oats 

Oats also contain a relatively high amount of arginine, so may be best avoided, especially if you feel one coming on. This is a shame, as oats make a tasty, nutritious breakfast!

7. Wheat

Another vital grain, but wheat unfortunately also contains high levels of arginine. This can be tricky to avoid, as it is found in most breads, pasta and baking – anything that contains flour really! Opt for gluten-free varieties of these foods as these will be free from wheat.

Don’t forget about muscle-building supplements

Muscle-building supplements usually contain a mix of amino acids to help the muscles grow. One of these is usually arginine, so make sure to check your supplements for arginine before you take them! 

The role of lysine

Lysine is another amino acid that is thought to help counteract arginine. Therefore the worst foods for you are those that are high in arginine and low in lysine. Those listed above have a low lysine to arginine ratio, so are not ideal for those who experience cold sores.

You may occasionally see claims that dairy is a rich source of arginine and should be best avoided. However, while dairy does contain a lot of arginine, it also contains a lot of lysine – usually more than twice as much! This balances out the arginine content.

When it comes to muscle-building supplements, I would recommend looking for one that doesn’t contain arginine, rather than simply counteracting the supplement with extra lysine. This is because the arginine found in your muscle-building supplement will likely be highly concentrated and hard to offset. 

The importance of balance

If you’re having trouble giving up these arginine-rich foods – which we’d understand as many of them are staple parts of a healthy, balanced diet – then you may want to consider taking a daily lysine supplement to help balance your arginine intake. This may be the best idea since many of the above foods are rich sources of vitamins, minerals and complex carbohydrates. 

One good strategy is to make sure to balance out your high-arginine foods with high lysine foods. For example, if you’re eating a meal that contains wholewheat pasta, try balancing this out with some fish, beans or avocado. 

If you’re going to cut out anything from the above list, I’d recommend nuts and chocolate, as these seem to be the worst offenders!