Joint N 11 contains quite a few good ingredients, the problem is that almost all of them need to be dosed in 5 to 10 times the volumes that they're in here. Turmeric root powder for example contains curcumin, which makes up about 8% percent of the extract at most.  Curcumin has been shown to be an effective supplement for joint pain, and a decent anti inflammatory, but it needs to be dosed in 500mg or above , and Joint N-11 will contain less than 50mg. This is a pretty consistent issues with the joint health supplement, seeing as it has a similar issue with ginger root powder, methylsulfonylmethane and rosemary.
There are a couple of positives in the Joint N-11 joint pain relief supplement, but we're down to bioperine (which has limited effect and is one of the least studied ingredients in here for joint pain), vitamin b3 and boswellia. The latter of which has a lot of studies backing it, and we generally rate it as a good ingredient in a lot of joint supplements, due to boswellia having been shown to be effective as an anti inflammatory and with a track record of improving joint function , but it is relatively cheap.
The worst inclusion is N-Acetyl-L-Cysteine, which has actually been linked to an increased risk of osteoarthritis.  The bright side is that the dose is so low here, it's not likely to impact anything.
Now, that's not to say that Zenith Labs Joint N-11 has nothing in it at all that's going to work, but considering it's high price point of $49.99 and that almost none of the effective ingredients are correctly dosed we don't recommend it. Especially if you're comparing it against the current best joint pain supplement on the market, FlexAgain , which is a little bit more expensive at $60 a bottle, but contains the correct dosages of ginger extracts, boswellia and curcumin as well as a host of more effective ingredients such as glucosamine and chondroitin (which are prescribed in some counties) as well as omega 3, more vitamins etc. You actually get 4 times the capsules for a months supply at $10 more which is some indication of the difference in dosages. They also offer a money back guarantee unlike Joint N11.
Customers reviews of Joint N-11 aren't bad, but they're not great either, it's mixed, there's a notable amount of negative Joint N-11 reviews from people who simply said it didn't work, which is to be expected. Although they also complained about the product being none refundable, and multiple health supplements in the joint and bone pain space offer money back guarantees when they're at the same price point as Joint N-11.
The people who did say that it worked noted that it took quite some time to be effective, which lines up with what we know about the efficacy of boswellia as a joint pain supplement. In that it generally becomes more effective after a 3 week period. 
|● Correct dose of Boswellia
|● Most ingredients are underdosed
|● B3 is a decent ingredient
|● Quite expensive
|● Some ingredients do nothing for joints
We wouldn't expect any notable side effects of Joint N-11 unless you're particularly sensitive to turmeric root powder, which some people are. In these cases it's possible that you could experience some mild nausea. The dose of vitamin b3 can also cause a mild but harmless red flush.
Currently we'd say that whilst Joint N 11 may have some effect on joint pain and joint function, the fact is that, there are much better options at this price point. In terms of effective ingredients and dosages you're really just getting vitamin b3, bioperine and boswellia, which can be purchased substantially cheaper, or in supplements that are about $20 for a month supply rather than $50. As such Joint N 11 scores low in terms of value.
Niacin (vitamin b3) 100 mg 625 % - This is a very high dose of niacin, and whilst preliminary studies do suggest that it can help reduce inflammation in OA suffers. It's a decent inclusion, but you should be careful if you're taking any other vitamin b supplements.  Not a bad inclusion, but b6 has more studies to back it's use for it's anti inflammatory properties.
Turmeric 200mg - As we've already stated this is simply far too low of a dose to be effective to improve joint function the way Joint N 11 promises.  500mg is the bottom end of curcumin to be effective and even at the generous end this is only likely to be about 20-30mg of curcumin.  This is disappointing as curcumin has actually been shown to be as effective enough to allow OA suffers to reduce other treatments notably and move to much weaker alternatives whilst using curcumin.
Ginger 200mg - Similarly to Turmeric, there's just not enough in Joint N 11 to be effective. Ginger root needs to be in dosages of 3 grams and up to work  as an anti inflammatory agent. There is a work around that some higher end supplements use, and that is by using a specific extract containing more hydroxymethoxyphenyl (the active ingredient that works in ginger). Most notably Eurovita 77 which is contains a similar amount of the extract has been shown to be as effective as 3 grams of ginger at 255mg . But, to get this much typically you need a galangal extract. There is only one joint pain supplement that we're aware of that currently utilizes this method (and has given us the 3rd party test certificates on request to validate it) FlexAgain. And even if Zenith Labs Joint N-11 did use a comparable extract, this still wouldn't be enough. All in all this is a shame as it's been shown to be even more effective than curcumin when dosed correctly, but most supplements simply don't include enough and Joint N-11 is no different.
MSM 200mg - Many joint pain supplements fall into the trap of including MSM, the catch is you need about 5 grams of it to be effective.  And 200mg is simply nowhere near enough to make any difference. It has however, been shown to be effective to reduce inflammation, stiffness and swelling.
N-Acetyl-L-Cysteine 100mg - So this is a bad ingredient all round, aside from the fact that supplementation of N-Acetyl has some links to increased OA risks, there's also the fact that there's little to no evidence in human trials to support it's use. There are rodent studies, but these suggested 100mg for every 2.2lbs of body weight. 
Boswellia Serrata 100mg - So, finally we have something positive to say about Zenith Labs Joint N-11, Boswellia is good for arthritis , gout  and pretty much anything where a natural supplement with an anti inflammatory effect is beneficial. 100mg is also within the effective range, so no real complaints here.
Basil Leaf Powder 100mg - Basil leaf is an odd inclusion, it's mostly known for it's effect on blood glucose  and doesn't really have much to do with joint health at all. It's may have some immune boosting benefits  as evidenced in a few small clinical trials, but that's about it. We're not really sure why it's included in here.
Rosemary Leaf Powder 100mg - Rosemary leaf is mostly used topically, it seems to be quite good when rubbed onto the effective area,  in at least there is a reasonable amount of studies to back it's use. But as an oral, most of the studies are in mice.  It does look like it may well be initially interesting as an ingredient, but it's typically dosed at 5mg/lb of body weight in mice. So, not a bad idea, but probably once again too low of a dose.
Soy Lecithin and Bioperine 50mg - Bioperine does have some evidence to suggest that it helps with inflammation, although it's relatively limited  as it would only need to be 20mg of this blend it's reasonable to assume it's correctly dosed. It's main benefit however, is that it does aid in the absorption of curcumin, substantially. The effect is nowhere near strong enough to multiply the bioavailability to the point it could make up for there being more than 10 times too little in Joint N-11, but it's a nice idea.  As for soy lecithin, there's some rat studies, but you'd need a lot more than is going to be in here if it did translate to humans effectively. 
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