Garlic & Lupus: What Foods are Rich in Ajoene, Allicin, and Thiosulfinates?

For people with lupus, what you eat is almost as important as the medicines that you take. Many people with lupus have heard that they shouldn’t eat garlic – why is that?

The truth goes beyond nutrition. Garlic has high concentrations of a type of nutrient called thiosulfinates. Many thiosulfinates affect the cardiovascular system and immune system, which could, potentially, cause flares and other problems for people with lupus. It is a little more complicated than that, as most nutrition-related issues are, and garlic is not the only food that contains thiosulfinates. 

What are Thiosulfinates? 

Thiosulfinates are a family of naturally occurring organic chemicals that have sulfur in their molecule structures. The thiosulfinate family include allicin and ajoene, which are naturally occurring substances that involve sulfur arranged in a specific structure. Many thiosulfinates are only formed when the plant that produces them is crushed or injured, allowing certain chemical compounds to react with each other.  

Thiosulfinates have an intense, eye-watering smells and potent antioxidant, antimicrobial, antiparasitic, and immune system-modulating effects. Plants produce these chemicals to protect them from harm, and eating plants with thiosulfinates like allicin and ajoene is a part of a healthy diet for many people. They’ve even been used as medicine for thousands of years! For people with lupus, however, these powerful medicinal health effects can be more complicated, and not always beneficial.  

What foods have high concentrations of them, and should you put serious effort into avoiding them? 

The Health Effects of Ajoene, Allicin, and other Thiosulfinates 

Ajonene, Allicin, and other thiosulfinates stimulate the immune system, protect against infections, and may also improve the body’s metabolism and prevent excessive weight gain. The exact mechanisms are likely due to complex interactions of multiple compounds in the body 

Ajoene and allicin are also well known to affect blood pressure, inflammation, and platelet function. This is why some people are told to avoid garlic while on medications like warfarin and other blood thinners and anticoagulants. They have also been proven difficult to extract and isolate from the food, which means that other molecules found in garlic, or in the food that they are cooked with, can change their effects in potentially unpredictable ways. Usually, this isn’t a bad thing – overall, the effects are positive in otherwise healthy people.  

However, the immune systems of people with lupus may be more sensitive to allicin and ajoene, which can cause flares in some people. It might also interact with lupus medications, making their effects less predictable or effective. 

Interestingly, some people with lupus find that garlic can actually help them, and thiosulfinate-containing foods can help make nutritionally balanced diets taste good.  However, there are other ways to season food and doctors generally advise against eating foods rich in thiosulfinates like allicin and ajoene because of this unpredictability. The other foods eaten with the garlic can also change the effects of the thiosulfinates or cause flares on their own. Eating garlic and other foods with thiosulfinates is highly individual, and people should take care and consult their doctors before re-introducing significant amounts of garlic into their diet. 

What is Allicin? 

Allicin is an organic chemical produced in the tissues of the plant. More accurately, the chemicals in the tissues of the plant become allicin when the plant is damaged and the inner parts of the plant are exposed to the air. Allicin is antibacterial and fungicidal, protecting the plant from infection along with repelling herbivorous animals. Researchers are looking into its potential use in antibiotics, agriculture, and as a blood pressure and cholesterol-lowering chemical. 

Allicin also is an anti-inflammatory. It slows or prevents tiny immune system molecules, called granulocytes, from entering body tissues and attracting or activating neutrophils, a type of white blood cell important to inflammation. It also appears to affect TNFalpha directly, which modulates inflammation – which means that, depending on the circumstances, TNFalpha is involved with increasing or decreasing inflammation, turning it up or down depending on other factors. This may be why garlic has mixed positive and negative effects for people with lupus.  

What is Ajoene? 

Ajoene is named after the Spanish word for garlic. Ajoene is what gives garlic its distinctive smell and taste, but a serving of garlic only has less than a percent amount of ajoene (0.1-0.5%.) Ajoene is a potent antimicrobial that protects the plant from infections.  

Currently, researchers believe that it works by making it harder for bacteria to ‘talk’ to each other, a process known as quorum sensing.  Quorum sensing helps bacteria colonies coordinate reproduction, nutrient transport, form biofilms, and secrete toxins – and yes, bacteria, even the ones that cause disease, do communicate between each other. When they can’t talk to each other very well, they can’t adapt to the body’s attempts to fight them off. Ajoene might have other medical applications too,  though it is still being researched. Some of these effects may be similar to NSAIDs. Whether this interferes with lupus symptoms or medications is currently unknown. 

Foods that Contain Ajoene, Allicin, and other Thiosulfinates 

As a major source of ajoene, allicin, and other thiosulfinates, garlic is usually focused on the most. However, there are other foods that contain these three compounds. 

What are Alliums? 

Garlic is part of a group of plants called alliums, which are plants that exist as bulbs or stalks with a sharp, astringent taste that is made milder by cooking. They all have these compounds in different amounts, which gives them their distinctive flavor. However, garlic is notable for having the highest concentration of these compounds, which gives it its distinct and intense taste and smell. This is why people with lupus are warned to be particularly careful about eating garlic, as it could affect their symptoms and interfere with their medications. However, other garlic- or onion-like plants might be wise to avoid, including: 

• Garlic  

• Onion 

• Chives 

• Scallions 

• Green onions 

• Leeks 

• and Shallots. 

What are Cruciferous Vegetables 

Broccoli, Kale, brussels sprouts, cabbage, bok choy, cauliflower and others also have thiosulfinates in them. However, they also are recommended for people with lupus because of their relatively high content of iron, calcium, fiber, vitamin C, flavonoids and other nutrients.  

A few other members of this family include: 

• Collard and Mustard Greens 

• Radish (including daikon, horseradish, and wasabi root) 

• Watercress 

• Arugula 

• Kohlrabi 

• and Chard. 

Although generally considered highly nutritious and beneficial for people with lupus, they can cause bloating and gassiness, and are overall very rich in vitamin K, which encourages clotting and interferes with medications such as warfarin.  

Should you eat Cruciferous Vegetables? 

Typically, yes. These vegetables are common, affordable, and nutrient-packed parts of a balanced diet. However, people with lupus might be sensitive to the health effects of some of these vegetables and react… but not react to others. The healthy foods for each person with lupus are sometimes found through trial and error, but it’s best to do so under the supervision of your medical team, which should include a nutritionist.   

Should you eat Garlic?

Garlic, Allium sativum, contains many thiosulfinates and other sulfur-containing natural chemicals. When cut, chewed, or crushed, chemical reactions occur that give it its distinctive smell, taste and even its health effects. In nature, these chemicals protect it from being eaten, though humans seek out its taste as a seasoning. Many cultures also use it as a traditional medicine,  and it has been used for thousands of years to treat arthritis, toothaches, coughs, and infections.  

Some people with lupus feel that garlic helps with their symptoms. Others find that it can make their symptoms worse or trigger flares. It’s a very person-by-person thing. However, generally doctors advise that alliums, and garlic in particular, should be avoided – at least in large quantities or particularly potent preparations (like raw or fresh.) Small amounts of alliums might also be fine for people with lupus, and still provide flavor. 

If you think that garlic or other thiosulfinate-containing foods might help you, you can re-introduce these foods to your diet and figure out what works for you through trial and error. If you are planning to re-introduce garlic into your diet, do so under the supervision of a medical team, which should already include a nutritionist.  

A way to reduce the risks can be in the preparation: Different ways of preparing these vegetables can change how the chemistry of the thiosulfinates works – with dried garlic powder, roasted whole garlic, and fermented garlic being notably less potent in taste and medicinal effect due to the chemicals degrading in different ways.  

Ajoene is fat-soluble, and eating it with a dietary fat (such as lard, butter, or oil) helps it absorb into the body more effectively. The more that is absorbed, the more it can affect the body – so using lower amounts of fats might be helpful to people with lupus who are exploring their sensitivity.