What is Phytic Acid?
Phytic acid aka phytate is found in whole grains, legumes, potatoes, nuts, and seeds. It is demonized in the paleo movement as an anti-nutrient, from which we should stay away.
The reason it’s referred to as such is that it binds minerals such as calcium, iron, potassium, magnesium, manganese, zinc, copper, and selenium, therefore, supposedly making them insoluble and thus unavailable for absorption in the intestinal tract of humans.
The picture isn’t so clear, however, and phytate also has a number of health benefits. This post is meant to demonstrate the phytic acid isn’t the villain it’s portrayed to be and is instead on the whole more healthful than not.
I don’t advocate supplementing with phytic acid since there’s an abundant supply of starches and plant foods (on a lectin avoidance diet, phytate is mostly removed).
Phytate is capable of being absorbed in our GI tract .
Phytate levels in serum peak 4 hours after ingestion .
Note that phytic acid, phytate, PA, inositol hexaphosphate and IP6 all refer to the same compound.
Before I speak about the benefits, I’d like to mention some drawbacks.
Phytate has been shown to inhibit digestive enzymes such as trypsin, pepsin, α-amylase, and ß-glucosidase . Alpha-amylase inhibition is used by diabetics to slow glucose absorption, so that’s actually not bad.
Phytic acid in excess is said to cause some GI issues, but I haven’t found scientific evidence of this. There were no harmful GI effects in mice fed significant quantities of phytate . I believe that the GI irritation from foods with phytate is actually coming from dietary lectins.
When I took phytase to break down phytic acid I didn’t notice a difference with regard to inflammation from food. However, when I took sugars that bind to lectins I did notice a significant difference. This is one way I realized that phytic acid wasn’t the main culprit for me, but rather lectins were. I’ve also consumed phytate supplements, without any ill effects.
Phytate can bind to certain minerals, which I discuss below, but for the most part, it’s not an issue. The main mineral that you should be concerned with is Zinc, which is why you should supplement with it if you have a plant-based diet.
1) It is an Antioxidant
Phytic acid has protected against alcohol-related liver injury by blocking free radicals and elevating antioxidant potentials .
The anti-oxidative action of phytic acid is as a result of inhibiting Xanthine Oxidase and by ‘preventing a formation of ADP-iron-oxygen complexes’ . It was also able to protect DNA from free radicals .
Roasting/cooking foods with phytic acid improved antioxidant ability .
2) Reduces Inflammation
Phytic acid was found to decrease the inflammatory cytokines IL-8 and IL-6, especially in colon cells [7, 8].
3) Induces Autophagy
Phytic Acid was found to induce autophagy .
Autophagy is a cellular process for degrading and recycling junk proteins .
It has recently been recognized as a principal response to cellular stress and an important regulator of neuronal function and survival .
It plays a role in the destruction of pathogens inside our cells .
As a ‘quality control’ process, autophagy is believed to be particularly beneficial in neurodegenerative disorders – Alzheimer’s, Parkinson’s, ALS and Huntington’s. This is because these disorders are, in part, characterized by the accumulation of misfolded disease-causing proteins .
Research suggests that autophagy is required for the lifespan-prolonging effects of caloric restriction  and for much of the health benefits of exercise . Inhibiting mTOR increases autophagy, which is part of the reason mTOR inhibition increases longevity .
4) Has Potential For Treating Multiple Cancers
Phytic acid was found to be anti-cancer against bone, prostate, ovarian, breast, liver, colorectal, leukemia, sarcomas and skin cancers [14, 15, 16, 17, 18].
Mechanism: suppressing the expression of matrix metalloproteinases (MMPs)  and telomerase .
5) Reduces Blood Glucose Levels
Studies show that phytate reduces blood glucose levels in mice and rats [20, 21, 22].
It works in part by slowing the rate of starch digestibility .
6) It is Neuroprotective
Neuroprotective effects of Phytic acid were found in a cell culture model of Parkinson’s disease .
It was found to protect against 6-Hydroxydopamine-Induced dopaminergic neuron apoptosis, which causes Parkinson’s .
By inducing autophagy, it can also protect against Alzheimer’s  and other neurodegenerative diseases.
7) Reduces Triglycerides and Increases high-density lipoproteins (HDL)
Studies have found phytate reduces triglycerides and increases HDL cholesterol (the good one) in rats .
8) Repairs DNA
It was found that phytic acid can enter cells and help DNA repairs breaks in the strands. This is a potential mechanism by which phytate prevents cancer .
9) Increases Bone Mineral Density
Phytate consumption had a protective effect against osteoporosis. Low phytate consumption is a risk factor for osteoporosis .
Adequate consumption of phytate may play an important role in the prevention of bone mineral density loss in postmenopausal women .
10) Protects Human Skin From UVB Exposure
UVB radiation damages skin cells, which can cause skin damage, cancer and suppression of the immune system .
Studies show that phytic acid protects cells from UVB-induced destruction and mice from UVB-induced tumors .
11) Can Protect The Gut From Toxins
Phytic acid supplementation increased gut transit time and resulted in more efficient absorption of nutrients (via ‘surface amplification’) .
Phytate also protects intestinal cells from certain toxins – at least in pigs .
12) Helps Prevent Kidney Stones
In rats treated with phytic acid, calcifications in their kidneys were reduced, which suggests a potential for preventing kidney stones .
Another animal study found that it inhibited the formation of calcium oxalate stones .
In a study on humans, phytate urinary levels in a group of active calcium oxalate stone formers were studied and compared with those found in healthy people. Urinary phytate was significantly lower for stone formers .
Low phytate levels may be why kidney stones are more of a problem in the paleo world.
13) Binds to Heavy Metals, Mycotoxins, Uranium, Iron, Manganese
Phytic acid is one of a few chelating therapies used for uranium removal .
Phytic Acid reduces the toxicity of mycotoxins, which may be explained by its antioxidant activity .
It also binds to heavy metals, iron, and manganese. Iron and manganese are nutrients that we normally get too much of, but not always. If we do have an excess, then that can have ill effects on our health.
14) Decreases Uric Acid/Helps Gout
By inhibiting the enzyme xanthine oxidase, phytic acid blocks the buildup of uric acid and can help prevent gout .
15) It is Anti-HIV
Phytate was able to inhibit the replication of HIV-1 in cell lines. PA was only beneficial on an early replicative stage of HIV-1-infection .
16) Increases The Bioavailability of Flavones
Phytate is a potential absorption enhancer for pharmaceuticals/supplements.
The oral bioavailability of isorhamnetin, kaempferol, and quercetin was enhanced by the co-administration of phytate.
The main mechanisms are related to their enhanced aqueous solubility and permeability in the presence of phytate .
How Phytic Acid Interacts With Minerals
There’s really only a few minerals that phytate binds to and as a result of the binding may potentially lead to health problems.
The minerals you should pay attention to are Zinc, and to a lesser extent, calcium and chromium.
Phytic acid can bind to zinc somewhat strongly and can cause GI problems, among other health issues. Zinc binding I think is the biggest issue and most people eating a plant-based diet should supplement with a small amount of zinc. Not only is phytate a problem because of zinc binding, but since eating such a diet contains a lot of copper, it will interfere further with zinc absorption. For these reasons, I supplement with 15mg of zinc glycinate and recommend this dosage to others, especially men. Women need less zinc, so it’s less likely to as big of a problem for them (RDA for men 19+ yrs old is 11mg and 8mg for women). 10mg of supplemental zinc should suffice for women.
Phytate can also bind to calcium, albeit not as strong as it binds to zinc. But not only have I not seen health problems as a result of this binding to calcium, I’ve only seen studies where it increases bone mineral density, which is unexpected. We obviously don’t have the full story. My wild guess is that it mainly binds to extra calcium that the body isn’t using and helps utilize or retain the rest of the calcium in some fashion. I supplement with 250mg 2X a day, not so much because of the phytic acid, but more because I don’t eat dairy and I don’t get the recommended level of calcium. If I did eat dairy, I’d consume maybe 150mg of calcium just to be safe (the RDA is 1000mg), because after all, phytic acid does bind to calcium. Linus Pauling Institute: “Phytic acid is a less potent inhibitor of calcium absorption than oxalate. Only concentrated sources of phytate, such as wheat bran or dried beans, substantially reduce calcium absorption.” So, I think people should focus on getting the RDA for calcium and maybe take a bit more if you consume a lot of phytates – just in case.
Binding of phytic acid to magnesium is not a good thing, but the foods with phytic acid are also usually rich in magnesium.
I’ve also seen a study where it binds to chromium and I was deficient in chromium at one point, so that may be a problem, too. Chromium deficiency is supposedly rare, but my experience possibly suggests otherwise, since I was eating a whole food diet with no added sugar (sugar causes excretion of chromium). It could be that I was deficient in chromium not because of phytic acid but because of decreased gut function from ingesting gluten or from a zinc deficiency. I take 100mcg of chromium GTF every day. These interventions are extremely cheap, simple and safe, so I find the drawbacks of consuming phytic acid to be very minimal.
Most people actually have too much iron. I’ve experimented with a starch-based diet for a while and my iron levels were still higher than the ideal range for anti-aging purposes, and that was without eating red meat. In addition, I also drank tea, kombucha, curcumin and a bunch of other iron chelators. Iron is in all foods and deficiency is usually caused by something else other than low consumption of iron. This is the reason you see some people donating blood to get rid of excess iron.
Menstruating women should monitor their iron levels more closely, however. I should also mention that people have different genetics with regard to how well they retain iron and I might be – genetically – a good iron storer.
Selenium is an important mineral that I supplement with since it’s good for autoimmune conditions of the thyroid. I take 100mcg daily, which is a conservative dosage. I also make sure not to eat brazil nuts or else I may be getting too much of it. Phytate doesn’t seem to be an issue for selenium, at least according to this study on baby chicks. If anything it seems to be a benefit. A quote:
“Phytate increased selenium in all tissues except muscle; it is not clear if this resulted from increased absorption or increased retention.”
The fact the phytate binds to manganese is a plus since people get too much manganese in a starch-based diet.
Copper absorption is actually enhanced by phytic acid in copper-deficient diets. I don’t know what would happen in diets that weren’t deficient in copper. I’d actually rather it bind to copper because starch-based diets are too high in copper. In any case, zinc supplementation should reduce copper absorption, so no worries here.
If you adopt a plant-based omnivorous diet you likely won’t have a problem, except for zinc. If you want to be safe you can take a small amount of chromium and calcium, though there’s no evidence that it’s necessary if you consume dairy and a balanced diet. This is a very small price to pay to get the health benefits of phytate. A review article on phytate and minerals in a vegetarian diet (not a diet I support):
Despite the apparent lower bioavailability of zinc, copper, manganese, and selenium in vegetarian diets because of the high contents of phytic acid and/or dietary fiber and the low content of flesh foods in the diet, the trace element status of most adult vegetarians appears to be adequate. Children, however, appear to be more vulnerable to suboptimal zinc status, presumably because of their high zinc requirements for growth and their bodies’ failure to adapt to a vegetarian diet by increased absorption of dietary zinc .
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