I have met quite a number of people, both vegetarians and non-vegetarians, who try to avoid eating beans, lentils and their derived products such as tofu and tempeh. While a handful of them do have genuine medical conditions, such as phenylketonuria, and were advised to reduce their consumption of beans and lentils; a majority of them simply acted out of misunderstanding.
In this post, I wish to introduce the benefits of eating beans and lentils and address some of the common “fear factors” about beans and lentils – putting them into perspective.
Benefits of Beans and Lentils
Beans and lentils belong to the legume family. Mature legumes are dried seeds found insides pods that hang from the stems of certain plants. The most common ones are soy beans, black beans, mung beans, kidney beans, red and green lentils, as well as chickpeas. Other types of legumes include peas, peanuts and alfalfa. Here are some of the compelling reasons to include beans and lentils in your diet [1]:
- Excellent source of protein.
- Good source of fiber.
- Low in fat.
- Most varieties provide half of our folate (B9) requirements.
- A good source of phosphorus, potassium, iron, zinc, calcium, and selenium.
- Contain Thiamin (B1), Riboflavin (B2), Niacin (B3), B5 and B6.
- Rich in antioxidants.
- Low Glycemic Index.
They are considered super foods by many health gurus [2]. Some beans, such as soy and black beans were found to have cancer fighting properties as well [3][4].
The inclusion of beans and lentils in diet is especially important for vegetarians, especially those who are on strict plant-based diet. This is because the beans and lentils can provide the essential amino acids of Lysine and Threonine that are lacking in grains, nuts and seeds, as well as Phenylalanine that is lacking in most green vegetables. Your body will not be able to generate new proteins if there is a lack of any of these essential amino acids!
Therefore, for those who are on strict plant-based diet, a good mix of vegetables, grains, nuts and seeds, as well as legumes should be included in the diet in order to get all the essential amino acids required by the body [5].
Why are people not taking beans and lentils?
Beans and lentils are such wonder food sources, why are some people not taking them? The two most common concerns are:
- They can cause joint pains, i.e. Inflammatory arthritis or gout.
- They are hard to digest and can cause bloated stomach.
Well, although there are some truths to these concerns, they have been exaggerated by many. Let’s look at the science behind to address these concerns.
Beans and lentils can cause gout
What is gout and what causes it? The following is the explanation provided by Mayo Clinic [6]:
Gout occurs when urate crystals accumulate in your joint, causing the inflammation and intense pain of a gout attack. Urate crystals can form when you have high levels of uric acid in your blood. Your body produces uric acid when it breaks down purines — substances that are found naturally in your body, as well as in certain foods, such as organ meats, anchovies, herring, asparagus and mushrooms.
What exactly are purines? Purines are actually natural substances that are found in our body cells as well as all foods. In fact, purines are the basic building blocks of our genes! Without purines, we are not able to regenerate cells and tissues. However, too much purines in our body can cause problems. Excess purines are being broken down into uric acids; and when the saturation of uric acids reaches a certain level, urate crystals will start to form. For treatment of gout, the patients are often advised to stay away from purine-rich food to help to reduce the serum urate level (sUA) in the body. Research has shown that patients can be free from the joint pains if they can maintain their sUA below 6 mg/dl (360 μmol/l) [7].
Many people have mistakenly taught that beans and lentils are purine-rich food and thus choose to avoid them to prevent the flare of gout. However, how true is this? It has been over exaggerated!!! For non-vegetarian, please take note, do you know that fish, chicken, steak, lamb, and pork all have higher purine content than beans and lentils?!
A serving (100g) of chicken meat contains 130mg of purines, and a serving of pork meat (100g) contains 119mg of purines. Anchovies, sardines and organ meats all contents very high purines per serving (>200mg). In comparison, a serving of cooked lentils contains only 74mg of purines, whereas, tofu has only 68mg. Some beans, like Garbanzo beans, have only 19mg of purines per serving [8].
In addition, a research paper published in 2004, which surveyed 47,150 men over a 12 year-period, concluded that higher levels of meat and seafood consumption are associated with an increased risk of gout, whereas moderate intake of purine-rich vegetables or protein is not associated with an increased risk of gout [9].
Therefore, for meat eaters, if you are scared of gout, please cut down your meat and fish consumption first before finding culprits in beans and lentils!
If purine-rich vegetables or protein is not associated with an increased risk of gout then why do vegetarians still suffer from gout?!
Well, food is usually responsible for only about 30% of the uric acid content in the blood serum [10]. Other risk factors for gout include alcohol consumption, obesity, hypertension, renal impairment, as well as medications (Diuretics, cyclosporine, aspirin, and niacin can all increase serum uric acid levels).
For vegetarians who are prone to gout attack, I often advise them to continue to take beans and lentils in moderation. If they happen to suffer from gout attack, then they should not only stop taking beans and lentils, but also a list of other vegetables including:
- Asparagus, cauliflower, mushrooms
- Fried foods, roasted nuts, any food cooked in oil (heated oil destroys vitamin E),
- Rich foods (cakes, sugar products, white flour products),
- Dark green vegetables, dried fruits, caffeine,
- Sprouts, beans, lentils, eggs, oatmeal, peas, yeast products
Therefore, there are many other factors that may contribute to gout, don’t blame it on beans and lentils alone!
Beans and lentils can cause bloated stomach
Another common complaint about beans and lentils is that they are hard to digest and can cause bloated stomach and burping. Some, especially those who have weak digestive systems, may also experience gas, heartburn, and reflux.
Most raw legumes and grains actually contain anti-nutrients on their surface. These anti-nutrients are natural compounds that interfere with the absorption of nutrients when ingested. Common anti-nutrients found in beans and lentils are phytic acid and enzyme inhibitors [12]. This is part of nature’s design to allow seeds, beans, grains, etc. to survive through the digestive tract of animals and be able to germinate in the droppings of animals and continue to propagate. However, there is an easy way to get rid of these anti-nutrients, simply soak the beans and lentils over night (at least 8 hours)!
Soaking is a simple and effective way to positively impact the nutritional quality of beans and lentils. Our ancestors knew this secret since over a thousand years ago. Scientist today has also confirmed this. In a paper published in 2003, Egyptian scientists found that soaking significantly decreased anti-nutrients such as phytic acid, tannins, phenols, α-amylase and trypsin inhibitors in four kinds of legumes (peas, chickpeas, faba and kidney beans), the digestibility of the proteins in these legumes have also been improved significantly.
Therefore, instead of shying away from beans and lentils, the sensible thing to do is to make sure that we prepare them properly.
Soak your beans and lentils overnight to unlock all the goodness in them!
Conclusion
In conclusion, beans and lentils are packed with nutrients, they are good for health. They are definitely not the main culprit that causes gout as many has thought. It is a misconception. Although they may be hard to digest if not prepared properly, this limitation can be overcome easily by soaking them overnight. Therefore, there is no reason to keep beans out of one’s diet!
References:
- Thomassian, M. (2007). “What Are Legumes?”, Dietriffic. Access from http://www.dietriffic.com/2007/09/09/what-are-legumes/“Dr. Perricone’s No. 4 Superfood: Beans and Lentils”. Read more: http://www.oprah.com/health/Beans-and-Lentils-Dr-Perricones-No-4-Superfood#ixzz2XIZTIPyA
- Zielinski, E. L. (2013). “Research links eating cooked black beans to lowered risks of cancer”. Natural News, Access from http://www.naturalnews.com/039890_black_beans_cancer_research.html#ixzz2XIlWmD52
- Rodriguez, O. (2010). “Is Soy Safe? Busting the Myths of a Nutritional Powerhouse”. Life Extension Magazine: July 2010. Access from http://www.lef.org/magazine/mag2010/mag2010_07.htm
- Barasi, M. (2007). Nutrition at a glance. Blackwell Publishing. UK
- Mayo Clinic (2011). “Gout: Causes”. Access from http://www.mayoclinic.com/health/gout/DS00090/DSECTION=causes
- Perez-Ruiz, F. (2009). “Treating to target: a strategy to cure gout”. Rheumatology. 2009;48:ii9–ii14. Access from http://rheumatology.oxfordjournals.org/content/48/suppl_2/ii9.abstract
- Davis B. (n.d.). “Diet and Gout”. Access from http://www.brendadavisrd.com/handouts.php?id=29
- Choi, H. K., Atkinson, K., Karlson, E. W., Willett, W., and Curhan, G. (2004). “Purine-Rich Foods, Dairy and Protein Intake, and the Risk of Gout in Men.” N Engl J Med. 2004 350(11): 1093-103. Access from http://www.nejm.org/doi/full/10.1056/NEJMoa035700
- Halevi, S. (n.d.). “Various food types and their purine content.”. Access from http://www.acumedico.com/purine.htm
- Physicians Committee for Responsible Medicine (n.d.). “Gout”. Access from http://www.tcolincampbell.org/courses-resources/article/gout
- Thehealthyhomeeconomist.com (n.d.). “Why You Must Soak Your Beans”. Access from http://thehealthyhomeeconomist.com/why-you-must-soak-your-beans/
- El-Hady, E. A. and Habiba R. A. (2003). “Effect of soaking and extrusion conditions on antinutrients and protein digestibility of legume seeds”. LWT – Food Science and Technology. Volume 36, Issue 3, May 2003, Pages 285–293. Access from http://www.sciencedirect.com/science/article/pii/S0023643802002177
Mung bean definitely causes gout. Every time I eat Mung bean, next day I have the gout attack. One cup of cooked mung bean will definitely cause gout the next morning in my case. One tablespoon has no effect.
Yes. If you have a flare-up of gout, it is advisable to avoid bean sprout as it can aggravate the condition. In fact, not only bean sprouts but also a number of other vegetables, which include asparagus, cauliflower, mushrooms, strawberry, beans, lentils, oatmeal, and peas.
However, bare in mind that gout is caused by crystallization of high concentration of uric acid in the blood. High purine content foods can increase the uric acid concentration in the blood. In general seafood and meats contain much higher purine content than beans, for example fresh salmon contains 260 mg/serving of purine and chicken meat contain 130 mg/serving of purine. In comparison, cooked soy bean has only 64 mg/serving, whereas beansprout is 80mg /serving. Therefore, it is more advisable to cut down the seafood and meat consumption, instead of blaming beans and beansprout as the culprit of causing gout.
Other foods that should be avoided include deep-fried or oily foods, roasted nuts, rich foods (cakes, sugar products, white flour products), dried fruits, as well as caffeine and alcohol.
I am facing gout pain. I thought that legume grains are increasing the uric acid level thereby making me more painful. But now it gave me some relief in my mind that I can consume them by improving the cooking methods by soaking overnight that also helps in reducing bloating too.
Thanks.
Good to hear.