b6 toxicity foods to avoid

RDA B6 Diet

The RDA B6 diet is exactly what it describes. We use a nutrition tracking website or app to maintain a diet that does not go over RDA. We also dont eat more than 30% of RDA at any given meal. There are too many varied ways of eating to have one specific meal plan. The RDA B6 diet then is your current way of eating adjusted to lower B6 intake to maintain RDA. In this section, we help you to help yourself with creating your diet. RDA stands for Recommended Daily Allowance. The National Institutes of Health has RDA for most people age 19 and above at 1.3 mg. Men over 50 have a RDA of 1.7 mg. Women over 50 have a RDA of 1.5 mg. Below is a chart for B6 RDAs from the National Institutes of Health vitamin B6 factsheet.

Weve already mentioned that a standard American diet contains 1.9 mg of B6. This doesnt take into consideration the superfoods we have added into our diets, the heavy protein diets or the super clean diets that have higher vitamin B6 intakes. There is nothing wrong with any of these diets, you just have to rethink them. The highest B6 foods are beef, chicken, turkey, pork, oily fish (salmon, tuna), potatoes, corn, brown rice, avocados, bananas and sunflower seeds. It is best to remove or severely limit all these HIGH B6 foods. The lowest B6 meats and proteins are goat, lamb, some white fish, shrimp, clams, lobster, crab leg, eggs and cheese. Processed meats like hot dogs, sausage, bacon, packaged sandwich meats will also be lower B6. Canned salmon is also a good choice for a lower B6 meat. You do not have to eat processed foods. These are listed for those who already eat processed. The protein powders that work best for us are pea protein, whey protein egg white protein. You dont have to add protein powders. These are listed for those who use protein powders. Please check for added B6 or other unnecessary ingredients in any protein powders. The lower B6 carbohydrates are rice noodles and white flour products (like white bread). The rice noodles are awesome in Italian dishes as well as Chinese, Vietnamese and Thai dishes. The white flour is made of wheat, but the B6 has been processed out and not added back in. Examples of white flour items are bread, pizza, crackers, pancakes, English muffins, bagels, cake, cookies. You will want to be careful with pasta. If the ingredients contain durum or semolina flour then it might be higher B6. You want to enjoy salty snacks. Almonds, pumpkin seeds, pretzels and crackers are all good choices for salty snacks. The best website we use for nutrient tracking is Cronometer. The free version tracks vitamins and minerals, plus many more nifty-needed items. You dont need to pay for Cronometer. Please visit the linked page for more detailed info about this awesome nutrient tracker.

It is common to lose weight while toxic on vitamin B6. Weve had many members in the group ask what foods are good to help put on weight. If you eat processed, then add in white flour products as mentioned above. If you dont eat processed then the suggestions are egg white protein powder, pea protein powder, butter, coconut oil, full-fat coconut milk, almonds, almond butter, cheese.

Although a 24 hour fast is not necessary, this question comes up often. A 24 hour fast once a week is fine. It is recommended that you fast from dinner to dinner. You still need to drink your salted water, coconut water and the Pedialyte. Since youre not getting salt from food it is also recommended that you add another 1/8 teaspoon salt to the water. The total daily amount of salt while fasting is about 1/2 teaspoon.

B6T RDA B6 Diet Dos

• Do stay at RDA B6 or slightly below it.
• Do keep your meals at around 30% RDA.
• Do count your coconut water in Cronometer.
• Do watch values of other nutrients especially, potassium, B12, B1 and iron.
• Do consider purchasing the B6T Smart Supplement. This supplement is only 25% RDA of most vitamins and minerals was designed specifically for the group. It has no vitamin B6. It also does not contain magnesium which is a strong vasodilator. This vitamin is a small boost of vitamins and minerals when your diet isnt enough. The vitamin was designed for the FB group. It gives the boost that most members wanted without the extreme excess of other supplements. #RethinkExcess.

B6T RDA B6 Diet Donts

• RDA B6 is for a reason. If you go lower, it can throw you into a horrible Rebound.
• Do not starve yourself. If you starve yourself, it will throw you into a horrible Rebound.
• Do not fast for more than one day.

Low B6 Foods

Many of you are overwhelmed with the idea of eating a lower B6 food diet. Many in the group have expressed that they dont know where to begin. We hear daily how the thought of creating a different way of eating is overwhelming. There are three ways to create your new way of living.

1. Use only Cronometer. Cronometer is a nutrition app/webpage that allows you to enter in your food choices. The B6 value will be determined for you. Remember to only use the NCCDB database (explained in the link). Enter in the foods you eat then determine your portion sizes based on the amount of B6. This takes the most time and energy.
2. Use Cronometer and the partial free spreadsheet in the group. The partial free spreadsheet was created by a member. The downside is that this member was an over 50 male. His RDA is higher than most people in the group. His percentages are off. Search the Facebook group with the term spreadsheet to find this free food list.
3. Purchase the $19.95 Quick Start Guide. The Quick Start Guide is the best $19.95 you will ever spend on your health. It is a summary of the most important pages of the website. Your brain-fogged mind will appreicate this. On top of the summary, it has nine pages of foods that are lower in B6. Below is a partial section of the Vegetable page. Although this example is for those who eat clean, there are other food sections for those who eat processed. This is a guide for most types of eaters. You will still use Cronometer to track your daily nutrients.

Bookshelf

Continuing Education Activity

This activity describes the toxicity associated with vitamin B6 at higher doses. It explains in detail the pathophysiology and toxicokinetics of vitamin B6 toxicity and patient symptoms. This activity reviews the evaluation and treatment of vitamin B6 toxicity and highlights the role of the interprofessional team in evaluating and treating patients with this condition.

Objectives:

• Identify the etiology of vitamin B6 toxicity.

• Outline an appropriate evaluation for suspected vitamin B6 toxicity.

• Review a reasonable differential diagnosis for patients presenting with signs and symptoms of pyridoxine toxicity.

• Select the treatment and management options available to the healthcare team for vitamin B6 toxicity.

Access free multiple choice questions on this topic.

Introduction

Vitamin B6 is a micronutrient required by the body. Vitamin B6 refers to multiple chemically similar compounds, of which pyridoxine is the most common and is the compound found in commercially available vitamin supplements. The body uses vitamin B6 in numerous enzymatic reactions, including neurotransmitter production, amino acid metabolism, glucose metabolism, lipid metabolism, hemoglobin synthesis and function, and gene expression.[1]In the United States, vitamin B6 intake from food averages about 1.9 mg/day.[2]Intake of food-based sources of pyridoxine will not cause toxicity.The only reported cases of vitamin B6 toxicity are from supratherapeutic dosing of supplements or iatrogenic.

Etiology

Almost all cases of vitamin B6 toxicity are from supratherapeutic dosing, either iatrogenic or laypersons self-treating with over-the-counter supplements. Daily dietary intake will not provide enough pyridoxine to causetoxicity. The daily dietary intake of vitamin B6 is approximately 1.9 mg/day in the United States.[2]Additionally, typical pyridoxine doses used for co-treatment with isoniazid are 10 to 25 mg/day. Pyridoxine toxicity typically manifests as neurologic symptoms, including paresthesias in the extremities and, in severe cases, difficulty with ambulation. This sensory neuropathy usually develops at doses of pyridoxine above 1000 mg per day. There are some case reports of sensory neuropathies at doses of less than 500 mg per day in patients taking supplements for months. However, none of the studies had sensory nerve damage at a daily intake below 200 mg of pyridoxine per day.[3]A rare cause of vitamin B toxicity is hypophosphatasia.[4]

Epidemiology

Vitamin B6 supplementation is a therapeutic option for a variety of medical conditions. Pyridoxine is used in supratherapeutic doses as an antidote to treat seizures from isoniazid toxicity.[5]It is used in therapeutic doses for hyperemesis gravidarumand isoniazid.[6][7]It is used as a nutritional supplement by the lay public for a variety of perceived health benefits, including morning sickness, cardiovascular disease, premenstrual syndrome, depression, and carpal tunnel syndrome.Evidence for efficacy for many of these uses is mixed.

Over-the-counter supplements are the most likely culprit for patients taking a pyridoxine level above the safe recommended upper limit. Often patients are unaware that high-dose pyridoxine could be harmful. One illustrative case report describes a patient presenting to a healthcare facility with peripheral neuropathy, and he reported taking vitamin B-complex supplements at fifty times the daily suggested allowance for ten years.[8]

According to the 2017 U.S. poison center data, there were 566 reports of using pyridoxine therapeutically as an antidote.[9]Additionally, 377 pyridoxine exposure cases were reported, including eight cases with only minor or moderate clinical effects. There were no serious outcomes or deaths reported.

Pathophysiology

Paradoxically the most common symptoms associated with vitamin B6 toxicity are similar to those with vitamin B6 deficiency. A patient will experience peripheral sensory neuropathy. Most commonly, this causes numbness in a stocking-glove distribution over the extremities. In addition to peripheral neuropathy, patients can experience ataxia and disequilibrium as well.[10]One large study found that patients also could experience hyperesthesia, bone pains, muscle weakness, numbness, and fasciculations.[11]

One study examined the role of pyridoxine toxicity on human cells to examine the neurotoxic effects further. They found that pyridoxine induced cell death in a concentration-dependent fashion and inhibited pyridoxal-5-phosphate dependent enzymes.[12]Thus it appears that the inactive form of B6, pyridoxine, competitively inhibits the active vitamin B6 form, pyridoxal-5-phosphate causing the symptoms of vitamin B6 toxicity to mimic the symptoms of vitamin B6 deficiency.

Toxicokinetics

After oral ingestion of pyridoxine, peak plasma levels are achieved in approximately one hour.[11]In the liver and other tissues, absorbed vitamin B6 forms are converted by the liver to pyridoxal 5-phosphate (PLP) and transported in the serum bound to albumin.[13]Oral doses of 100 mg of pyridoxine, pyridoxal, and pyridoxamine, the majority are excreted unchanged in the urine.[14]

Several drugs have interactions with vitamin B6 and can interfere with their levels. These medications typically lower the level of pyridoxine and leave to vitamin B6 deficiency and not toxicity. Isoniazid, cycloserine, penicillamine, and L-dopa all form complexes with vitamin B6, limiting its bioavailability. Oral contraceptives are associated with lower pyridoxine phosphate levels in a subset of women.[15]High doses of pyridoxine may decrease the blood levels of phenytoin and phenobarbital.[3]

History and Physical

History and physical exams are essential for identifying patients with vitamin B6 toxicity. Most patients will have neurologic symptoms and be seeking an evaluation for sensory neuropathy.A detailed medication reconciliation, including over-the-counter supplements, is needed.Since many over-the-counter supplements can have different doses of pyridoxine, having patients bring in medication and supplement bottles can be beneficial to ascertain the exact dosage of vitamins in a particular product.

The physical examination should include a thorough neurologic exam, including sensory, motor, gait, reflexes, cranial nerve testing, and muscle strength. Patients will typically present with bilateral sensory or motor changes, although a unilateral presentation is possible if there has been previous trauma or neurologic injury to an extremity.

Evaluation

Serum pyridoxine levels are typically less than 30 mcg/L. Patients with signs or symptoms of neuropathy should receive a referral to neurology or other specialists that can perform nerve conduction velocity studies.The diagnostic evaluation will typically start with the patient reporting signs and symptoms of peripheral sensory neuropathy.The workup of peripheral neuropathy is important to evaluate and rule out other etiologies of neuropathy.

Treatment / Management

There is no specific treatment or antidote for pyridoxine toxicity. Treatment involves cessation ofsupplemental pyridoxine promptly following diagnosis, symptomatic management, and supportive care for any continued or irreversible symptoms. This could include physical therapy when appropriate.

Also, the recommended daily allowance for different age groups should be kept in mind while prescribing B-6:

• 0.5 to 1 mg in children

• 1.3 mg daily for youngadults

• 1.7 mg daily for men older than 50 years

• 0.5 mg daily for women older than 50 years

Differential Diagnosis

The differential diagnosis of vitamin B6 toxicity is broad and includes deficiency or toxicity of other vitamins, including vitamin B12 as the symptoms are similar. Other causes of peripheral neuropathy merit consideration include diabetes mellitus, autoimmune disorders (lupus), chronic liver disease, end-stage liver disease, HIV/AIDS, hypothyroidism, Lyme disease, lymphoma, monoclonal gammopathy, syphilis, porphyria, drugs (amiodarone, digoxin, lithium, isoniazid), and toxins (heavy metals, ethanol, organophosphates). Exposure history and the temporal course will help differentiate many of these etiologies. Additional laboratory testing and nerve conduction velocity studies may also be helpful.

Prognosis

Prognosis is usually favorable, with symptoms resolving or decreasing whensupratherapeutic pyridoxine has been discovered and stopped.Neuropathy from massive exposures can cause long-term disability or death. Neurologic dysfunction improves following discontinuation of vitamin Bsupplementation and usually resolves within six months. Some patients do not recover.

Complications

Patients typically experience symptoms of peripheral neuropathy,dermatoses, photosensitivity, dizziness, and nausea with long-term intake of dosages above 250 mg/day. Additional morbidity would include ataxia and dysesthesias.

Deterrence and Patient Education

Patients should receive education regarding vitamins and minerals derived from their daily diet. Counseling should be provided to patients interested in supplementing pyridoxine and discussing risk with higher-end dosing. Medical professionals employing pyridoxine as therapy will typically use smaller doses.

Pearls and Other Issues

• Vitamin B6 is used to treat multiple medical conditions and is available as a supplement over the counter.

• Vitamin B6 toxicity symptoms mimic vitamin B6 deficiency.

• The classic presentation of pyridoxine toxicity is peripheral sensory neuropathy.

• It is helpful to obtain a thorough history and ask about supplements and dosages.

• Vitamin B6 toxicity is seen with vitamin supplements but not from dietary intake of foodstuffs.

• Symptoms generally improve after discontinuing supplementation.

Enhancing Healthcare Team Outcomes

Healthcare is a team enterprise consisting of multiple medical professions, and various interactions within this process influence patient care and outcomes. The most crucial factor for pyridoxine toxicity is to recognize peripheral neuropathy as a critical feature.This will trigger a comprehensive interview to get additional information on past medical history, medications, supplements, and occupational and environmental exposure history. Allied health professionals can assist in patient care outcomes by completing the medical history and current medications and supplements. Obtaining a detailed vitamin supplement history, including drug names, dosages, and length of time a patient has been taking medication, can be key aspects in identifying vitamin B6 toxicity.

References

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Disclosure: Adam Hemminger declares no relevant financial relationships with ineligible companies.

Disclosure: Brandon Wills declares no relevant financial relationships with ineligible companies.