Calcium Fructoborate: Benefits, Side Effects, Best Time to Take It & More

Calcium fructoborate

(Boron supplement)

Evidence: Reasonable
Possible Benefits: Reasonable
Safety: High

What is calcium fructoborate?

Calcium fructoborate is a supplemental form of boron, a trace mineral often taken for improving bone health and increasing free testosterone. This article is about the main benefits of calcium fructoborate, its potential side effects, the best time to take it, and more.

What does calcium fructoborate do for the body?

The main and only benefit of calcium fructoborate is that it provides highly absorbable elemental boron.

Boron is not classified as an essential mineral which means you should not need it to survive.

However, this mineral still has many functions in the body. Its two most important functions are related to bone health and hormonal health.

Boron plays an important role in osteogenesis (the formation of bones) and in preventing a vitamin D deficiency.

This mineral also helps free up testosterone by lowering SHBG (sex hormone-binding globulin). This effect is highly useful for people with low free testosterone relative to their total testosterone.

Possible benefits

It is important to note that all of the potential benefits mentioned below are dose-dependent. Generally, the higher the dose, the more pronounced the effects are. However, they do reach a plateau at a certain point. We will discuss the best dosing protocol later in this article.

Major benefits

Increased free testosterone – Boron can significantly lower SHBG (sex hormone-binding globulin), which releases testosterone bound to it and turns it into free testosterone. While more research is needed to show how effective this mineral is for increasing free testosterone, the improvement appears to be on average about 30% after a week of supplementation. This effect is mainly beneficial for people with low free testosterone relative to their total testosterone.

Minor benefits

Reduced inflammation – Calcium fructoborate supplementation has a positive effect on some inflammatory cytokines but whether or not this leads to any practical health improvements is not yet known.
Reduced rates of kidney stones – This is likely due to boron’s ability to prevent vitamin D deficiency to some extent. If you already get enough vitamin D, calcium fructoborate won’t be as beneficial in this regard.

Possible side effects

These side effects are dose-dependent. The risk for them increases (often linearly but sometimes exponentially) as you increase the dose. Some of the side effects only apply to very high doses.

Diarrhea – Diarrhea caused by this supplement is not dangerous (assuming it doesn’t lead to severe dehydration) and usually only occurs if you take very high doses at once.
Nausea – Just like diarrhea, this side effect is not dangerous but can be unpleasant.
Boron toxicity – While severe toxicity is rare, taking high amounts of calcium fructoborate could lead to chronic toxicity over time. Those suffering from toxicity may experience kidney problems and testicular harm. Doses of multiple grams (5-6 grams in infants and 15-20 grams in adults) can result in death. That is why it is best to avoid very high doses. Specifically, you want to stay below 10 mg a day unless you have a great reason to take more.
Contamination – Contaminated supplements are uncommon in the USA and other well-regulated countries. However, if you wish to buy products from China, India, or other countries without strict regulations, beware that the supplements may be contaminated. Either way, you need to choose the brand you order from wisely. It is highly recommended to check the certificates or read through some reviews for the specific product before you buy it. The FDA (Food and Drug Administration) has the power to regulate dietary supplements but can only do so after they have been on the market for a while. That’s because supplement companies are not obligated to announce to the FDA when releasing a new product on the market. The FDA has to discover the product and test it for potential impurities, which can take a lot of time. During that time, the supplement can be sold on the market even if it’s impure. Also, supplement companies can change their manufacturers without announcing it to the FDA.

Who should not take calcium fructoborate?

You should probably avoid taking the supplement if you:

already consume enough boron from food
experience a severe adverse reaction after taking the supplement
are on a tight supplement budget (since there are more cost-effective supplements on the market for most people)

Who will benefit the most?

You should consider taking the supplement if you:

have low free testosterone relative to your total testosterone
have low total testosterone and are unable to increase it (calcium fructoborate cannot directly increase total testosterone but it can raise your free testosterone to normal levels in this scenario)
are deficient in vitamin D
have a high budget for supplements (assuming that the supplement doesn’t contain impurities, it appears to be safe in most cases and rarely does more harm than good if you stick to regular doses)

Types of boron supplements

The different types of boron supplements include:

Boron citrate
Boron glycinate
Boron aspartate
Boron gluconate
Calcium fructoborate
Ionic boron
Borax

Other than Borax, all supplemental types of boron are easy to absorb and safe at normal doses. Boron citrate is the best type to take for most people because it is the most studied type with the best safety profile. Borax is the cheapest form but it should be avoided as higher doses can lead to kidney failure and other side effects not associated with other types.

How much calcium fructoborate should you take?

For most people, 3-6 mg appears to be the best daily target. This amount should provide most of the benefits without meaningful side effects.

Some people may benefit from doses higher than 6 mg. These include men with very high body weight and men with very low free testosterone and high levels of SHBG.

The upper safety limit is 20 mg/d. To stay on the safe side, don’t take more than 10 mg daily unless you have a great reason to do so. Higher amounts may cause problems if you take the supplement for a prolonged period.

Food sources of boron

An average adult in the developed world consumes about 1 mg of boron daily. Most boron people consume comes from fruits, vegetables, tubers, and drinking water.

A regular avocado contains about 1 mg of boron. The same can be said about 40 grams of raisins, 50 grams of peanuts, 2 apples or peaches, or 2 cups of broccoli.

As long as you eat these foods or foods similar to these, you should get the 3 mg/d from food alone and not need to take a supplement.

Best time to take calcium fructoborate

Calcium fructoborate is water-soluble, so you don’t have to take it with food to absorb it well. Taking the supplement with food is better if it causes stomach upset when you take it on an empty stomach.

Whether you take the supplement in the morning or the evening doesn’t matter. It does not interrupt your sleep in any way.

Interactions

Vitamin D
Boron increases the absorption of vitamin D and helps correct a vitamin D deficiency to some extent.

Where to buy calcium fructoborate

Amazon is the best option for ordering calcium fructoborate supplements in most countries. They offer some very affordable products backed by many positive reviews. Also, you can choose from a wide range of brands without having to search through other markets on the internet.

Beware some brands display the dosage per serving instead of per pill or capsule. Therefore, you may accidentally buy something less potent than you intended. Do not fall for this marketing trick.

FAQ

You can take the supplement daily and do not need to cycle it. However, it is certainly not a problem if you don’t take it daily. Not taking the supplement every once in a while could lead to better absorption.

All of these options are fine. The two most important things to consider are the price and dosing. Powders are almost always the cheapest form. However, you may need a highly accurate scale to dose them correctly (preferably 0.001g). You can get one for as little as $20 from Amazon. Dosing the powders also takes some time that can add up over months or years. The disadvantage of capsules is that they often contain bovine gelatine, which rarely comes from an ethical source.

Yes. The nutrient doesn’t impact your sleep in any negative way in the short term.

The supplements should not become harmful once they exceed the expiration date, but they can lose potency over time.

Keep the supplements in a cold, dark, and dry place, and they should remain just as potent for many months or even years.

The supplement doesn’t directly reduce acne, unfortunately.

While toxicity is rare, too much boron in the system can cause some health problems, such as nausea, diarrhea, and more severe side effects like kidney failure in rare cases. It is best to stay below 20 mg a day to prevent these side effects.

You may need more of the nutrient if you:
– have low free testosterone relative to your total testosterone
– have low total testosterone and are unable to increase it (boron cannot directly increase total testosterone but it can raise your free testosterone to normal levels in this scenario)
– are deficient in vitamin D

The half-life of boron in the body is about 21 hours but the nutrient stays in your system for only about a day after you consume it.

In the long term, it typically takes about two weeks of taking the supplement to begin noticing the benefits related to increasing free testosterone.

Most calcium fructoborate supplements on the market are vegan-friendly but always check the label to be sure. If you buy the mineral in a capsulated form, beware that the capsules often contain animal-based gelatine. Instead, find a brand that puts its products into cellulose capsules.

The nutrient is water-soluble, so you don’t have to take it with food to absorb it well.

No, it doesn’t. The supplement does not interfere with fasting in any significant way.

References

Most of the information provided in this guide is supported by scientific research that can be found and verified in the PubMed medical library. We highly encourage you to use the library to verify anything said in this article. We excluded from consideration studies that are either confounded or have a high conflict of interest.

TABLE OF CONTENTS