Instaflex Review of Joint Pain Research

Instaflex is a joint pain supplement that you may have heard of from its TV and radio ads. The product is said to be “scientifically formulated to help relieve stiff, achy joints and support cartilage repair.” Unlike several arthritis supplements that you may have heard of―like Supple for example―Instaflex has a clinical study showing that it might help some people. So, in this review, I want look at the Instaflex clinical study and give my thoughts about it and the various ingredients in Instaflex―as well as mention other things I discovered while I was investigating this supplement. I also want to address questions people might have about this product. For those who feel Instaflex is expensive, I think I know what its active ingredient might be.


Instaflex Ingredients

According to the product website, 3 capsules of Instaflex have the following ingredients (there are 90 capsules per bottle):

Ingredient Amount % DV
Glucosamine sulfate 1500 mg N/A
MSM 500 mg N/A
White willow bark 250 mg N/A
Ginger root extract 250 mg N/A
Boswellia serrata extract 125 mg N/A
Turmeric extract 50 mg N/A
Cayenne 40M H.U. 50 mg N/A
Hyaluronic acid 4 mg N/A

N/A = no daily value established


Other ingredients in Instaflex include: rice flower, gelatin, vegetable magnesium stearate, and silicon dioxide. The label also indicates that Instaflex contains crustacean shellfish (specifically shrimp and crab), which is where the glucosamine sulfate is derived from.

Instaflex does not contain gluten.

Unlike other arthritis supplements I see, Instaflex does not contain chondroitin sulfate. I actually liked this because I’m not convinced it helps arthritis pain, and because for men, chondroitin sulfate may be linked to prostate cancer.


Instaflex Research

The Instaflex website ( does not show any published peer-reviewed studies on Instaflex itself.  This is odd because when I checked the National Library of Medicine for “Instaflex,” I immediately discovered a study published in 2013 in the Journal of Nutrition titled, A commercialized dietary supplement alleviates joint pain in community adults: a double-blind, placebo-controlled community trial. I’ve linked to the entire study so you can read it. Here is a summary of the investigation:

  • The study was supported by a grant from Direct Digital LLC, the makers of Instaflex; however, they took no part in the investigation. None of the researchers have any connection to Direct Digital, either. That’s good.
  • This was an 8-week study involving 100 men and women with a history of joint pain. People randomly received either 3 capsules of Instaflex or 3 capsules of a placebo per day for 8 weeks.
  • People refrained from using arthritis meds, NSAIDs, or joint pain supplements during the study.
  • No side effects were reported.


  • 37% of people taking Instaflex reported overall significantly less joint pain compared with those who took the placebo (16%).
  • Those with knee joint pain reported the greatest reduction in pain.
  • Joint pain reduction was noticed by the 4th week of the study.
  • There were no changes in inflammation markers like CRP or in people’s ability to walk quickly for more than 6 minutes (a common test for arthritis).


My Thoughts On The Study

It is interesting that people reported that they felt less joint pain, even though blood tests revealed no significant changes in inflammation (CRP levels). CRP is said to measure inflammation in the body. According to this finding, Instaflex didnt reduce CRP levels – and so it didnt reduce inflammation either.

This might mean that changes― not measured by researchers―might be responsible for people feeling less joint pain. I don’t know. I’m speculating.

In addition, one might think that if the joint pain was less, people should be able to walk faster during the 6-minute walking test―but they didn’t.

It’s possible that the inability to walk fast for 6 minutes (a common test for arthritis pain), could be due to poor aerobic ability or poor muscle coordination in subjects. This would make sense but again, this is speculation on my part.

One possible problem with this study is that the subjects were those who had “self-reported history of joint pain in the knees, hip, ankles, shoulders, or hands.” In other words, they just said they had pain, rather than being formally diagnosed with arthritis by a doctor.

But, what was the cause of their joint pain?

Was it osteoarthritis or rheumatoid arthritis, or something else? The study does indicate that “only 31%” of the people reported that they had arthritis.  But what about the rest of the people? Also, the exact cause of joint pain for the people in the study was not confirmed by a doctor. So, we don’t know what their medical situations really were. This is a problem. This study would have been better if we knew what the cause of the joint pain was.


Instaflex Ingredient Research

Aside from the single study summarized above, I’m not aware of any other Instaflex research. Still, the study appears for the most part to be well done. Research or not, the ingredients in Instaflex do show up in other supplements that I’ve already reviewed. For those who want to know more about the ingredients in Instaflex, I will point you to the other reviews where you can discover more information if you choose to. Here’s a breakdown of those reviews:

Glucosamine Sulfate. For more information, see:

MSM. For more information, see:

White Willow Bark. This is an aspirin like compound. For more information, see:

Ginger root extract. For more information, see:

Boswellia. For more information, see:

Turmeric. For more information, see:

Cayenne. For more information, see:

Hyaluronic acid. For more information, see:


Instaflex Side Effects

In the Instaflex clinical study summarized above, no side effects were reported. I am also not aware of any side effects either. That said, here are some theoretical side effects based on the ingredients.

The Instaflex website indicates that the glucosamine comes from shrimp and crab. Those who are allergic to shellfish should talk to their doctor first.

People who take blood thinner medications should talk to a doctor. Several of the ingredients in Instaflex have blood thinner properties. The ingredients I identified that might do this include:

  1. Glucosamine sulfate
  2. White willow bark
  3. Ginger
  4. Turmeric

Because of this, stop taking Instaflex at least 2 weeks before surgery. This is a wise precaution for all supplements you take as well.

Glucosamine sulfate might raise blood sugar in some people so those with diabetes or other blood sugar issues should discuss this with a doctor for more information.

There is some evidence that turmeric might exacerbate gallbladder problems. How significant this is I don’t know, but it’s probably best for those with gallbladder problems to speak to their doctor for more information.

When I searched online, I read that Instaflex might be associated with sores around the lips of the mouth. My guess is this might be due to the cayenne in Instaflex. Cayenne is, after all, “cayenne pepper.” The Instaflex label indicates that the product has 40,000 Heat Units of cayenne in 3 capsules. To me, Heat Units (H.U., as it’s referenced on the label) is a tip-off that it might burn the mouth.

The product website also indicates that people who are pregnant or nursing or who take medications or who have heart problems should see their doctor before taking Instaflex. That statement includes a lot of people—so when in doubt, ask a doctor first.


Ingredients With The Most Evidence

Here is a list of the ingredients in Instaflex that have been studied to help arthritis pain:

  • Glucsamine sulfate
  • MSM
  • White Willow Bark
  • Ginger
  • Boswella
  • Turmeric

Of these, I think the main active ingredients might be – in order – glucosamine sulfate, MSM and maybe white willow bark, although its possible that the other ingredients provide additional benefits.

Ingredients That Don’t Work

Here are the ingredients that I feel don’t help arthritis pain, and my reasons why I feel this way:

Cayenne. The bottle indicates that Instaflex contains cayenne at a concentration of 40M H.U. For those who are curious, the “M” refers to thousand and “H.U.” refers to Heat Units. So, 40M H.U. means 40,000 Heat Units. That said, I don’t feel it helps because the arthritis research involves applying cayenne cream to the skin. Creams are different than supplements that are taken orally.

Hyaluronic acid. The evidence for hyaluronic acid helping arthritis is based on injections―not supplements. I see no good proof that hyaluronic acid supplements help arthritis.


Who Makes Instaflex?

The company behind Instaflex is Direct Digital LLC which has offices in Boston and North Carolina. As can be seen from its website――this is a sales and marketing company. There is nothing wrong with this, but I wanted to mention it for those who thought the company was a laboratory facility.

On the website, they give this US address for the company: MS #730 913 West 2900 South Salt Lake City, UT 84119. I believe the “MS” in the address may stand for either mail stop or mail slot. As can be seen from the link I provided, this appears to be some sort of a warehouse facility.

Direct Digital markets many supplements including a product I reviewed previously called Nugenix, a supplement for men over 40. See my review of Nugenix for additional information.

While there is no Better Business Bureau rating for Direct Digital, when I wrote this review, there is a rating for Instaflex. As of 2/4/14, the Better Business Bureau gives Instaflex a rating of “A.”” Do look at the BBB page for more information. Update. The BBB has changed the rating for this company. See the BBB file.


The Free 14-Day Trial

You may have heard TV or radio ads for a free 2-week trial of Instaflex. Here are the details from the product website of the free trial.

You have to pay $4.99 shipping/handling for them to send you the 2-week trial. They say it typically takes 4 days to receive the 2-week trial bottle. Thus, the 14-day trial period starts 18 days after you order it. That makes sense. You must give them a credit card to receive the 14-day free trial.

Note. The website says that there is only 1 free trial bottle per address allowed. If it’s discovered that a household has received more than 1 free bottle, their credit card used will be charged $37.49.

If you do not call customer service within 18 days of ordering the free trial, the credit card you gave them will be charged $74.88 plus any tax that’s due―and they will automatically send you a 30-day supply of

Instaflex Joint Support, 90 Count
List Price: $69.99
Price: $41.81
You Save: $28.18
that by purchasing Instaflex through the website, people waive their rights to sue the company in court or take part in class action lawsuits if anything bad were to happen. Rather, people must go through binding arbitration.

This is similar to the Terms and Conditions I noticed for the supplement called Nugenix, which is also marketed by Direct Digital.


Questions and Answers

As part of my review, I’ve noticed a lot of questions were being asked online about Instaflex. Let me try to address some of those questions briefly here:

Q. Will Instaflex help a torn rotator cuff muscle?

A. Probably not. Instaflex is a supplement for joint pain. Torn muscles of the shoulder are different than joint pain from arthritis.

Q. Does Instaflex re-grow cartilage?

A. There is no good proof that the ingredients in Instaflex re-grow or repair joint cartilage.

Q. Where does the gelatin in Instaflex come from?

A. Call Instaflex customer support for this. My guess is the gelatin comes from pigs or cows.

Q. Can Instaflex help dogs or cats with joint pain?

A. I’m not aware of any dog or cat research for Instaflex. I suggest showing the ingredients to a veterinarian who can provide the best answers.

Q. Does Instaflex help joint pain other than in the knees?

A. It’s hard to say. Most glucosamine sulfate research finds that it seems to help the most with knee arthritis pain. Even the Instaflex study summarized above noted that those with knee pain had the greatest relief. The assumption people often make is that this benefit translates to less joint pain elsewhere in the body such as the hips. I don’t think anyone can say with certainty that this is because arthritis is a complex disorder.

Q. Will instaflex prevent arthritis?

A. There is currently no proof that Instaflex or any other glucosamine supplement prevents arthritis. There is some evidence that glucosamine sulfate (not Instaflex) might slow the progression of arthritis. Would Instaflex do this? Maybe, but it’s difficult to say without research.

Q. Is it ok to take Instaflex if I have diabetes?

A. Talk do your doctor if you have diabetes or blood sugar problems. Glucosamine sulfate contains sugar (glucose) which may be a problem for some people.

Q. Will Instaflex help back pain?

A.  Instaflex has not been studied for its effects on back pain. I feel that whether it helps or not would depend on what is causing the back pain. Instaflex does contain white willow bark which has an ingredient that’s similar to aspirin. According to the Instaflex clinical study, the amount of this ingredient is equal to about 1/4 of an aspirin tablet. Theoretically, this might offer some pain relief. Regardless, it’s best to see a doctor/physical therapist about the cause of the back pain.

Q. Can Instaflex help gout pain?

A. Gout is a form of arthritis but it’s not the type of arthritis that glucosamine sulfate is shown to help. I don’t think Instaflex (or glucosamine sulfate) will have any effect on gout pain.

Q. Can Instaflex help rheumatoid arthritis?

A. It’s unfortunate that the Instaflex clinical study did not identify the causes of the joint pain people had. If they did, we might have been able to have an idea if it helps or not. That said, glucosamine sulfate has been studied to help osteoarthritis, not rheumatoid arthritis (RA). Could other ingredients in Instaflex have pain-reducing effects that might help RA? Maybe, but without proof, it’s unknown.

Q How long before it works?

A. According to the website, they say most people should notice a difference in 7 days but that they recommend giving it 3 months to know for sure. While I am happy for those who feel a difference in 7 days, the clinical study of Instaflex noted that it took 4 weeks before people started to notice a difference. Because of that, I’m not sure if most people who use the 2-week free trial of Instaflex will notice a difference. Much of the glucosamine research I’ve seen indicates that it may take 4–8 weeks before a difference in pain is noticed.


The Other Instaflex Supplements

In addition to the Instaflex joint support that I am reviewing here, if you go to the product’s website you see that there are other related supplements that also have the Instaflex name. They are:

I’ve looked at the ingredients in these products and I don’t believe they are needed. There is also no published research on any of these other products. I’ve linked to these products on Amazon if you want to see the reviews by others, and because they are less expensive there also. My opinion is to save your money on these other products.


Does Instaflex Work?

Instaflex is different than many other joint pain supplements in that it has a published, clinical trial showing it might help some people. According to that study, those with knee joint pain might benefit the most from Instaflex, although it’s possible that pain in other areas of the body might be helped as well.

Joint pain is a vague phrase, so I want to point out that I believe that joint pain stemming specifically from osteoarthritis is the only condition that Instaflex is likely to help. Fortunately that is the most common type of arthritis. I think it’s wise for people to be diagnosed with osteoarthritis before investing in Instaflex supplements. I see no good evidence that Instaflex helps other arthritis conditions, although I admit that it’s possible that some of its ingredients might work through different chemical pathways.

Many of the ingredients in Instaflex seem logical to me, so I would not be surprised by those who said “it works.” I would also would not be surprised by those who said “it didn’t work” because the research is not unanimously positive when it comes to arthritis supplements.

While it’s possible the unique cocktail of ingredients in Instaflex might work within 7 days as the product website states, I think it’s more likely for it to take 4–8 weeks, which is in line with most of the glucosamine sulfate research―and the Instaflex clinical study.

I believe the main active ingredient in Instaflex is probablyglucosamine sulfate, although some of its other ingredients might add other benefits. Unfortunately, I’m not aware of any Instaflex vs. glucosamine sulfate research at this time to test my theory. I believe Instaflex can be expensive, especially if purchased from the product’s website. As such, consumers should compare prices at their local stores and online before buying.

Here is Instaflex on Amazonfor those who are interested and want to see what others are saying.

What do you think?


  1. joy says

    Hi All, I take all those supps individually, and have been hearing a lot about this instaflex and don’t like the auto ship if one does not call customer service….went thru this same mess with anatabloc…..

    I still take some anatabloc and like my results with Great Lakes Hydrosylate…sorry it’s not reviewed here….

Leave a Reply and join the conversation.