It’s allergy season again and I decided to do a bit more experimentation with food elimination from my diet. Based on the title of this post you may have guessed that coffee was one of these foods. Stay tuned for a future post on the results of the seasonal allergy food elimination process.
I have tried yerba mate before but have not used it in place of coffee for an extended period of time. However, with my decision to fully remove coffee for a period of time I wanted to find a satisfactory replacement. Luckily, I have also been really into Tim Ferris’ book, The Four Hour Work Week, which lead me to his use of yerba mate for creative writing. I was intrigued so I did some research and found a good deal of information on yerba mate tea, and also discovered Guayusa and Guarana teas which I will write about in another post.
Yerba Mate and Stimulants
If you have not heard of yerba mate in the past few years, you have probably been out of the health trend loop. This is a traditional South American drink, very common in Argentina and Brazil, which contains a higher level of caffeine than most other teas, about half the amount present in coffee. Caffeine is part of a family of central nervous system stimulating molecules called Xanthines. Others members of the xanthine family are theobromine and theophylline. Interestingly, coffee only contains caffeine and theobromine; however, yerba mate contains all three xanthines (1, 2), the combination of which is said to produce a more sustained stimulant effect than coffee. When drinking yerba mate I find that I do not get the immediate kick like I do with coffee and but the ‘buzz’ is more sustained. I also had some mate the other day at around 8pm and it did not affect my sleep in any way. I have not tried it the way the Tim Ferris suggests, in the above noted article, but the combination of mate with some alcohol sounds intriguing. Healthy vodka and redbull anyone? Just kidding, but I can very much see it helping with sustained concentration and the creative process.
Yerba Mate and Cancer
There are many health benefits tied to yerba mate consumption; however, there is also some scary information out there about it possibly being a cause of mouth and esophageal cancer (3, 4). Given the presence of this concerning information, let’s address this topic right of the bat. First and foremost, the majority of this information stems from epidemiological studies, and we all know that such studies are not sufficient for us to draw any conclusion about ultimate cause. For instance, it is said that high south american consumers of yerba mate also fall in other high risk cancer categories such as smokers and heavy drinkers. Given the fact that it is impossible to control for all the compounding factors in these type of studies, the best we can conclude is that we need to perform more specific research to determine actual mechanisms by which it may cause cancer
Nonetheless, the possibility of yerba mate as a cancer cause is still there so lets talk specifics. Some studies (3) and sources suggest that the relation is due to the fact that in South America, yerba mate is prepared with very hot water and also drank at a high temperature with a metal straw that also transmits the high temperature of the drink. Basically, drinking or eating anything at a temperature that could damage your tissues (ie. burn) can lead to cancer; then, add a burning hot metal straw in the mix and we are bound for some trouble. This is only one suggested mechanism for yerba mate’s relation to cancer, the second suggested mechanism is much more concerning. Polycyclic Aromatic Hydrocarbons (PAH) are molecules created when something is burned (food and wood are 2 simple examples) and some PAHs are classified as carcinogens. One of the main PAHs that is a known carcinogen is benzo[a]pyrene and has been shown to be present in yerba mate brands in fairly high concentrations (3). One article even said that consuming yerba mate in the traditional amount (which is a fairly large amount) could cause exposure to benzo[a]pyrene amounts similar to that of 100 cigarettes. For some reason I find this to be a bit of an exaggeration, and we would probably also need to take into account the differences between the method of delivery to our body (ie. direct smoke vs. aqueous solution).
OK, I am a bit depressed now so let’s get to the good news on the cancer point. It has been identified that the processing of yerba mate leaves is the likely culprit of the high PAH concentration. Yerba mate is traditionally dried over flames from burning wood; however, there are certain brands that are well aware of the PAH issue and are taking steps to reduce PAH levels. For instance, you can get air dried (non-smoked) Yerba Mate products that have much less PAH in them (3). Here are some product suggestions:
Benefits of Yerba Mate
With all the negative stuff out of the way, let’s talk about the evidence in support of the multiple benefits of yerba mate. Although everything I could find seemed to be studies on rats, it is still evident that there is significant antioxidant activity in yerba mate. There is evidence that it can reduce oxidative stress, DNA damage, lipid oxidation (5, 6, 7) as well as evidence that it can prevent certain forms of cancer via it’s anti inflammatory properties (6, 7). One study even showed the anti-cancer properties of a component of yerba mate on human colon cancer cells (7). Before I continue I do want to mention that some of the noted studies were using extracts of compounds found in yerba mate, and some were using yerba mate tea as part of the subjects drinking water.
Yerba mate has also been shown to reduce insulin resistance, control weight, positively impact blood lipids, and have antimicrobial properties (8, 9, 10, 11).
While much of the available evidence comes from animal models, it is clear that yerba mate has demonstrated antioxidant, anti-inflammatory, anti-mutagenic, lipid-lowering, and antimicrobial activities. It is even suggested that we could consider this drink for a wide range of other chronic inflammatory conditions (11).
But is Yerba Mate Safe?
Well, since the evidence is mixed, some pointing to it as a cause of cancer and some pointing to it as preventing cancer and inflammation, the choice is left up to you to determine if the pros outweigh the possible cons. However, keep in mind that if you are sourcing a high quality product that was processed without smoke, you are likely fully in the clear, at least that is my opinion and I will continue to drink my mate.
The Barefoot Golfer