While plant-based foods are beneficial to health in numerous ways they are not free from risk. Plants produce a variety of chemicals to protect them from pests, external environments. And considerable numbers of such chemicals go against human health also. Some such chemicals inhibit nutrients absorption. That means although you consume those nutrients you will not have the benefits as your body doesn’t absorb them. Some have toxic results which can lead to disease. However by adopting the right strategies you can overcome or minimize those risk burdens. We will know here some common health risks of plant-based foods: Overcoming strategies.
Health risks of plant-based foods: Overcoming strategies
Anti-nutrients
You will see seeds, beans or legumes, nuts, etc last for a longer period due to their anti-nutrient contents. Plants give protections to their seeds with anti-nutrients from the external environment. But those anti-nutrients don’t work well for you. Have a look at such anti-nutrients.
Phytate or Phytic acid
Phytate of plant-based foods reduces mineral absorption such as iron, zinc, magnesium, and calcium from foods. The Source of phytate mainly includes seeds, grains, and legumes. (1, 2, 3) Although phytate reduces mineral absorption it also has antioxidant properties and may provide protection against kidney stones and cancer. (4, 5)
Lectins
Lectins are found in seeds, legumes, and grains. It also interferes with nutrients absorption and promotes gastrointestinal problems. (6, 7)
Also, read 6 lesser-known the root causes of acidity or heart and how to overcome those.
Tannins
Tannins, a class of antioxidant polyphenols may inhibit digestive enzymes and affect the utilization of nutrients. On the other hand, it also inhibits the growth of many fungi, yeasts, bacteria, and viruses. (8,9)
In nature, tannins are found in plants, including tree bark, leaves, spices, nuts, seeds, fruits, and legumes with varying amounts. Plants produce tannins to protect them from pests. Some of the richest and common dietary sources of tannins include tea, coffee, chocolate, wine, berries, barley, grapes, and some more. Although it has antioxidant and anti-inflammatory properties, overconsumption could lead to negative side effects. (10, 11) Therefore you should consume such foods in moderation.
Protease inhibitors
Found mainly in beans, legumes, grains, and seeds inhibit enzyme protease that further impairs protein digestion. (12)
Strategy to reduce anti-nutrients
Activating enzymes in plant foods that contain anti-nutrients deactivates anti-nutrients. Sprouting, water soaking for a longer time usually activates enzymes in foods and brings down the anti-nutrients parts. (13) That’s why you should make your beans, legumes, lentils water socked and make them sprouted or soft enough. Rinse them 2-4 times thoroughly in water and draining the water. And boiling or cooking further degrades anti-nutrients.
Similarly, fermentation also reduces anti-nutrients but you should know the proper way of fermentation. (14, 15, 16)
Similarly, water soaking helps to reduce anti-nutrients in nuts. That can be further drying and low-temperature roasting. For cucumber, squash, etc you need to peel off the skin.
Oxalates in plant foods and kidney stone
Although there are other types of kidney stones in the study most of the kidney stones contain calcium oxalate. (17) Due to better solubility, your body absorbs soluble oxalate better than insoluble sources. And after absorption, it circulates in the blood to form calcium oxalate. (18) From their most kidney stones are formed when absorbed oxalate binds to calcium while urine is produced by the kidneys. (19)
All most all plants contain oxalate with varying amounts. And most of those foods are also very healthy. However, some plant foods contain a high amount of oxalate. We will come to this in the lower part.
Remember that sugar consumption also increases uric acid and can cause chronic kidney disease. Read about some best available natural calorie-free sweetener as a sugar alternative.
Your gut health determines how much oxalate you absorb
People with healthy gut absorb only a little amount of oxalates and the majority passed out. Therefore most healthy people may consume oxalate-rich foods without major problems. But when there are impaired gut health and increased permeability in gut absorption of oxalate also becomes high. (20, 21)
Moreover, while the human body lacks enzymes to breakdown oxalate gut bacteria degrades oxalates. And thus a healthy gut ecosystem helps to oxalate a reduction in your body. (22, 23) In fact, a study found the risk of developing IBS was 2.48 times higher in patients with kidney stone disease than in those without the disease. (24) Not only oxalate, but scientists also found gluten degrading bacteria. That may explain while gluten posses a threat to some but may not for all. With the rapid change of environment and natural imbalance, the bacterial ecosystem to the human body is also changing. We are now in the different bacterial ecosystems than our ancestors had. That is another reason for the development of chronic diseases.
Here again, it fits that you are what you absorb rather than what you eat. Thus a healthy gut environment is very important not only for preventing oxalate absorption but also to maintain overall gut health.
Strategies to reduce oxalate intake and absorption
According to the National Kidney Foundation “Moderating intake of foods that contain high levels of oxalate may be beneficial for people who form calcium oxalate stones, the leading type of kidney stones. A common misconception is that cutting the oxalate-rich foods in your diet alone will reduce the likelihood of forming calcium oxalate kidney stones. While in theory, this might be true, this approach isn’t smart from an overall health perspective.” (25)
Dietary calcium binds with oxalate from oxalate containing foods and thus prevents the absorption of oxalate through the intestine. Therefore pairing of dietary intake of calcium or calcium-containing foods with foods containing a high level of oxalate prevents absorption of oxalate and making it less likely to form kidney stones. While taking calcium, vitamin D3 and K2 play very crucial roles in calcium absorption, circulation, and right placement. Other nutrients important along with calcium include magnesium and phosphorus. While calcium facilitates muscle contraction magnesium exerts relaxation.
Also read why without vitamin K2, vitamin D and calcium can be disastrous.
Cooking reduces oxalate content from foods
While you boil foods that contain high oxalate it causes the oxalate to leach out from foods into water. Once you drain the water leached oxalates go with it. However, this process causes the loss of other nutrients and makes food less taste-full. You may add other ingredients with them to make food tastier.
In a study boiling markedly reduced soluble oxalate content by 30-87% followed by steaming 5-53%. (26) Another study reported boiling reduced oxalate components more than 50% from vegetables like spinach, carrot, beetroot, white bean, red bean, and soybean. While boiling with water to reduce oxalate, different vegetables need different times. (27)
To ensure about leaching of oxalate from foods, boiled vegetables need to be soft enough.
Other strategies to reduce oxalate from foods include
- Drinking enough water,
- Reducing sugar intake as it can increase kidney stone risk
- Limiting salt intake as excessive salt intake reduces the fluid volume in the body
- Limiting oxalate-rich foods
- Reducing excessive ingestion of animal proteins
Moreover, if you do exercise, use a sauna bath and similar activities that cause sweat and reduces water content in the body also reduces urine volume needs to hydrate enough to maintain the urine volume. (28, 29)
Your body also breakdown vitamin C to oxalate. Therefore high intake of vitamin C also increases the amount of oxalate in urine. (30)
Know more about vitamin C health benefits, daily limit as well as food sources.
Foods with high oxalate content (31,32, 33)
Some foods but not limited to that contains high oxalate includes as:
Fruits:
- berries
- kiwis
- figs
- purple grapes
- Star fruit
Vegetables:
- Dark green vegetables
- rhubarb
- okra
- leeks
- spinach
- beets
- Swiss chard
- Turnip greens
- Kale
- Sweet potato
- Endive
Nuts:
- almonds
- cashews
- peanuts
- soy products
Grains:
- bran flakes
- wheat germ
- quinoa
Beverages:
- cocoa
- chocolate
- tea
Foods that contains high or fair amount of calcium
Vegetables:
- broccoli
- watercress
- kale
- okra
Legumes:
- kidney beans
- chickpeas
- baked beans
- navy beans
Fish:
- sardines with bones
- whitebait
- salmon
There also other foods that contain calcium. You may think why I am not including milk here as milk has a rich source of calcium. In many producers, present days cow’s milk is not the same as the old day’s milk with a change of milk protein components. Moreover, lactose intolerance exist with many.
Goitrogens in cruciferous vegetables
Cruciferous veggies have many health beneficial effects like anti-inflammatory, antioxidant, antibacterial, anti-fungal, neuroprotective, glucose, and lipid-lowering effects. Crucifers also improve cardiovascular health and prevent cancers. (34, 35) While cruciferous vegetables give many benefits to human health, they are not completely risk-free. Some crucifers contain a high amount of goitrogenic compound, that interferes with your iodine uptake. And as a result that can lead to impaired thyroid function. However, crucifers have varying amounts of goitrogens and a small amount of goitrogen doesn’t affect.
Read more about vegetables that contain a high or low amount of goitrogens as well as how to reduce goitrogens from crucifers.
Bottom-Line
Probably there is nothing that is completely risk-free. It all depends on the weight of good over bad. Plant-based foods are usually known for cancer-preventive, anti-inflammatory, anti-oxidant, cardioprotective, longevity, and more. Although plant-based foods posses some health risk, adopting the right strategies you can minimize and overcome them.
Disclaimer: Information provided here are generalized information for informational and entertainment purpose only, not intended to provide one to one health consultation or replace practice of a qualified practitioner.Different people may have different health condition and may have different reaction to the same food. Hence it has been advised to consult with health care provider before application of any of above information Source and references: 1.Schlemmer U, Frølich W, Prieto RM, Grases F. Phytate in foods and significance for humans: food sources, intake, processing, bioavailability, protective role and analysis. Mol Nutr Food Res. 2009;53 Suppl 2:S330–S375. doi:10.1002/mnfr.200900099 2.Ma G, Li Y, Jin Y, Zhai F, Kok FJ, Yang X. Phytate intake and molar ratios of phytate to zinc, iron and calcium in the diets of people in China. Eur J Clin Nutr. 2007;61(3):368–374. doi:10.1038/sj.ejcn.1602513 3.https://www.healthline.com/nutrition/how-to-reduce-antinutrients#section2 4.https://www.healthline.com/nutrition/phytic-acid-101 5.https://www.precisionnutrition.com/all-about-phytates-phytic-acid 6.Vasconcelos IM, Oliveira JT. Antinutritional properties of plant lectins. Toxicon. 2004;44(4):385–403. doi:10.1016/j.toxicon.2004.05.005 7.Nachbar MS, Oppenheim JD. Lectins in the United States diet: a survey of lectins in commonly consumed foods and a review of the literature. Am J Clin Nutr. 1980;33(11):2338–2345. doi:10.1093/ajcn/33.11.2338 8.King-Thom Chunga, Cheng-I Wei b Michael G Johnson c, Are tannins a double-edged sword in biology and health?, Trends in Food Science & Technology,Volume 9, Issue 4, April 1998, Pages 168-175, https://doi.org/10.1016/S0924-2244(98)00028-4 9.Chung KT, Wong TY, Wei CI, Huang YW, Lin Y. Tannins and human health: a review. Crit Rev Food Sci Nutr. 1998;38(6):421–464. doi:10.1080/10408699891274273 10.https://www.healthline.com/nutrition/tannins-in-tea 11.https://dspace.uevora.pt/rdpc/bitstream/10174/18018/1/DETERMIN ANTS%20OF%20TANNIN_final_corrections.pdf 12.Rackis J.J., Wolf W.J., Baker E.C. (1986) Protease Inhibitors in Plant Foods: Content and Inactivation. In: Friedman M. (eds) Nutritional and Toxicological Significance of Enzyme Inhibitors in Foods. Advances in Experimental Medicine and Biology, vol 199. Springer, Boston, MA https://doi.org/10.1007/978-1-4757-0022- 0_19 13.Preet K, Punia D. Antinutrients and digestibility (in vitro) of soaked, dehulled and germinated cowpeas. Nutr Health. 2000;14(2):109–117. doi:10.1177/026010600001400203 14.Ramadass B, Dokladny K, Moseley PL, Patel YR, Lin HC. Sucrose co-administration reduces the toxic effect of lectin on gut permeability and intestinal bacterial colonization. Dig Dis Sci. 2010;55(10):2778–2784. doi:10.1007/s10620-010-1359-2 15.Lajolo FM, Genovese MI. Nutritional significance of lectins and enzyme inhibitors from legumes. J Agric Food Chem. 2002;50(22):6592–6598. doi:10.1021/jf020191k 16.Gupta RK, Gangoliya SS, Singh NK. Reduction of phytic acid and enhancement of bioavailable micronutrients in food grains. J Food Sci Technol. 2015;52(2):676–684. doi:10.1007/s13197-013-0978-y 17.Finkielstein VA, Goldfarb DS. Strategies for preventing calcium oxalate stones. CMAJ. 2006;174(10):1407–1409. doi:10.1503/cmaj.051517 18.Chai W, Liebman M. Effect of different cooking methods on vegetable oxalate content. J Agric Food Chem. 2005;53(8):3027– 3030. doi:10.1021/jf048128d 19.https://www.kidney.org/atoz/content/kidneystones_prevent 20.https://med.nyu.edu/medicine/nephrology/sites/default/files/ne phrology/Calcium%20oxalate.pdf 21.Knauf F, Ko N, Jiang Z, et al. Net intestinal transport of oxalate reflects passive absorption and SLC26A6-mediated secretion. J Am Soc Nephrol. 2011;22(12):2247–2255. doi:10.1681/ASN.2011040433 22.Abratt VR, Reid SJ. Oxalate-degrading bacteria of the human gut as probiotics in the management of kidney stone disease. Adv Appl Microbiol. 2010;72:63–87. doi:10.1016/S0065-2164(10)72003-7 23.Sivasamy Gomathi et. al., Screening of Indigenous Oxalate Degrading Lactic Acid Bacteria from Human Faeces and South Indian Fermented Foods: Assessment of Probiotic Potential, The Scientific World Journal, Volume 2014, Article ID 648059, 11 pages https://doi.org/10.1155/2014/64805 24.Erdem E, Akbay E, Sezgin O, Doruk E, Canpolat B, Cayan S. Is there a relation between irritable Bowel syndrome and urinary stone disease?. Dig Dis Sci. 2005;50(3):605–608. doi:10.1007/s10620-005-2482-3 25.https://www.kidney.org/atoz/content/kidneystones_prevent 26.Chai W, Liebman M. Effect of different cooking methods on vegetable oxalate content. J Agric Food Chem. 2005;53(8):3027– 3030. doi:10.1021/jf048128d 27.Muhammad Shoaib Akhtar, Beenish Israr, Nighat Bhatty & Amanat Ali (2011) Effect of Cooking on Soluble and Insoluble Oxalate Contents in Selected Pakistani Vegetables and Beans, International Journal of Food Properties, 14:1, 241- 249, DOI: 10.1080/1094291090332605 28.Finkielstein VA, Goldfarb DS. Strategies for preventing calcium oxalate stones. CMAJ. 2006;174(10):1407–1409. doi:10.1503/cmaj.051517 29.https://www.kidney.org/atoz/content/kidneystones_prevent 30.Knight J, Madduma-Liyanage K, Mobley JA, Assimos DG, Holmes RP. Ascorbic acid intake and oxalate synthesis. Urolithiasis. 2016;44(4):289–297. doi:10.1007/s00240-016-0868-7 31.What Is a Low-Oxalate Diet? by Peggy Pletcher, MS, RD, LD, CDE and reviewed by Katherine Marengo, LDN, RD https://www.healthline.com/health/what-is-a-low-oxalate- diet#high--oxalate-foods 32.Finkielstein VA, Goldfarb DS. Strategies for preventing calcium oxalate stones. CMAJ. 2006;174(10):1407–1409. doi:10.1503/cmaj.051517 33.https://www.stjoes.ca/patients-visitors/patient- education/patient-education-k-o/pd-9447-oxalate-in-food.pdf 34.https://universityhealthnews.com/heart-health/the-best- cholesterol-lowering-food-cruciferous-vegetables/ 35.https://hms.harvard.edu/news/greens-genes
