Peanut Butter Causes Cancer?

November 4th, 2007 by Paul Johnson

Bodybuilders are suggested to eat a high amount of good fats in their diet for hormonal and joint health, and for a good source of calories. Peanut butter is a very common source of fat for most bodybuilders in their diet. Most eat natural peanut butter because it doesn't contain hydrogenated fats. Peanut butter is considered a good source of fat because it is low in saturated fat and high in monosaturated. The truth is, peanut butter is really not that healthy long term.

Why peanut butter can cause cancer:

Unfortunately a mold commonly winds up growing on peanut butter. This fungus Aspergillus flavus releases a cancer causing metabolic product (mycotoxin) called aflatoxin B1, which is a officially recognized carcinogen (cancer causing compound). Workers around peanuts even have to wear protection because of the health hazard. It is common knowledge that farmers and animals around peanuts have increased liver cancer.

How much of this fungus and to what degree it converts to the mcycotoxin aflatoxin seems to depend on where the peanuts are grown and how they are stored and for how long. Peanuts have less of this problem if they are farmed in dry climates, as the fungus seems to thrive in humidity. Other foods have this fungus growing on it such as walnuts and grains, but peanut butter and corn seem to be the worst afflicted foods.  The risk of peanut butter giving liver cancer is a bit exaggerated by some. But most bodybuilders consume it everday, often in high amounts, which could be a problem.

Alternatives to peanut butter:

Almond butter is the best food alternative for peanut butter. Flaxseed oil would even be better, but it's not a substitute in food as a butter. Almond butter actually has higher omega 3's than peanut butter anyways and isn't contaminated with this fungus. Almond butter is not as tasty as peanut butter, but at least you know you won't be posioning your body. If you decide to use peanut butter, see if you can get peanuts grown in dry areas, to help reduce or eliminate fungus contamination.

  1. Sharleen on April 22nd, 2008

    This all really goes back to the ‘everything in moderation’ theory. Anytime you over-emphasize any one food or food source the risk can end up outweighing the benefit. For example, the whole soy craze then scare. It has a lot of benefits but consuming it several times a day for an extended period of time carries it’s own risks as well. Certain fuel ratios are, of course, critical in whatever your health goal is, but it is not beneficial to eat any one food excessively in the same way it is not generally beneficial to cut out particular foods completely.
    The mold in peanuts has long been known to be the root cause of peanut allergies so it goes to follow that inundating your body with peanut butter may not be the best idea even if you don’t have an obvious intolerance to it.

  2. admin on April 22nd, 2008

    Thanks for your response sharleen. You are right that its all about moderation. Bodybuilders often consume tons of protein cause its calorie dense and it is a good source of healthy fats.

  3. dthcnine on July 17th, 2008

    thanks for the great information…

  4. Dave on August 7th, 2008

    Is there any indication that populations consuming roasted (as opposed to raw) peanuts have increased cancer risk? One would think that roasting and processing peanuts at high enough temperature would kill much of the mold. Note that peanuts also naturally contain resveratrol, a known anticarcinogenic compound. Ultimately, I would like to see any evidence that peanut butter causes cancer in humans before taking it too seriously, but I do acknowledge that the possibility should not be dismissed outright.

  5. admin on August 15th, 2008

    Whether or not it kills the mold, it doesn’t change the fact that the carcinogen left by the mold is still there.

  6. j on September 12th, 2008

    Truth is the government tests for this mold an the average jar of peanut butter has 14 parts per billion 1000 times less than what is considered harmfull. So eat all the peanut butter you want and dont listen to the witch doctors who tell you otherwise.

  7. Maria Belinda Chavez on November 16th, 2008

    I always eat peanut butter is really true cant cause cancer to the liver?

  8. Alice on February 22nd, 2009

    Another good substitute for peanut butter is sunflower seed butter, which is not as expensive as almond butter, and which can easily be made into sunflower seed butter sauce (like peanut sauce) or just eaten on sandwiches etc.

  9. Xavier on May 12th, 2009

    The origin for peanut butter causing cancer goes back to the Ames Test of Mutagenicity in which it was discovered that natural products had higher mutagenicity rates than synthetic chemicals (herbicides, etc).
    The mutagenicity rate refers to the rate at which compounds cause mutations to form.
    Hence high mutagenic levels means higher chances of causing a mutation in our DNA and can consequently cause cancer.
    As said before, one must consume products in moderation.

  10. ken on November 11th, 2009

    Peanuts by themselves aren’t any more likely to cause cancer than any other single food, but they can get infested with a mold that produces a substance called aflatoxin. Aflatoxin is a very potent carcinogen that causes liver cancer. This may be why you heard that peanuts can cause cancer. In the U.S., peanuts are routinely screened for aflatoxin after harvest, and if any is detected, the entire load of peanuts is quarantined and taken out of the human food supply. There have been outbreaks of liver cancer in Africa, Asia, and the South Pacific, especially among children, who eat a lot of peanut butter, but there have not been any known outbreaks in the U.S.

  11. ken on November 11th, 2009

    Just wanted to give credit to above statement to Yahoo answers


  12. Nathan on September 17th, 2010

    I hope peanut butter doesent cause cancer because i’ve consumed approxametly 5 pounds of peanut butter a week for the past 3 years

  13. rosco mack on April 19th, 2011

    I have recently converted from eating large amounts of organic peanut butter to almond butter, due to the fact that even the health-food peanut butter has been roasted, and in high- heating the peanuts the healthy oils are rendered rancid and unsuitable for consumption! Unless you are buying raw peanuts (tested mould-free), and processing yourself, forget it.. That risk/ hassle simply isn’t worth it, so try nutritious almond butter people, it works!!

  14. admin on April 28th, 2011

    @rosco I think even some of the almond butter out there is roasted too isn’t it? I guess it would be best to find almond or peanut if its unroasted.