NMN (nicotinamide mononucleotide) is a supplement that helps boost NAD+ levels in the body, which is needed to keep our cells healthy as we age.
NMN is generally well-tolerated, meaning most people don't have serious side effects when they take them, yet some people online report mild side effects or feeling sluggish after they stop taking it.
For the most part, NMN is safe and easy for most people to take. In the few studies that have been done, there haven't been any serious side effects, but some people report minor issues like headaches, stomach upset, and nausea if taken in extremely high doses.
These aren't unique to the NMN compound and are a pretty common side effect with a lot of supplements, especially when taking capsules on an empty stomach. It’s usually a good idea to take NMN with a light meal to help avoid any stomach problems.
Side Effects of NMN
The main concern customers & users have mentioned online (but is not documented in clinical trials) is feeling tired or having brain fog when they stop taking NMN.
This might happen because their NAD+ levels drop back to baseline when they're no longer boosting it with NMN. Since NAD+ naturally decreases as we age, some people feel less energetic than before they started their NMN supplementation.
Can NMN Affect Sleep?
Some people have said that taking NMN affects their sleep, especially when they take higher doses.
To stay on the safe side, you should start NMN doses around 250-300 mg daily and increase your dose to higher levels to suit your wellness goals over several weeks — or until your body adjusts to the supplemented NMN. There's no hard evidence to back this up, but one theory is that NMN could throw off your circadian rhythm (your body’s internal clock) by increasing NAD+ levels at the wrong time.
NAD+ levels are usually higher during the day when we need more energy, so taking NMN too late might keep you up at night.
A few people also mention feeling more irritable or even experiencing "rage" after taking high doses of NMN, but again, there’s no scientific proof of this. It could be the body adjusting to higher NAD+ levels, but more research is needed.
Can NMN Cause Cancer?
Right now, there’s no evidence to suggest that NMN causes cancer.
In fact, NAD+ is important for helping the body repair DNA, which is an important mechanism our body has in preventing cancerous mutations. However, since we don’t have long-term studies yet, it’s always good to be cautious, especially for people who have a higher risk of cancer or are already undergoing cancer treatments.
You'll want to check with your healthcare practitioner to see if NMN supplements are a good fit for your health goals.
Side Effects in NMN Supplements
Different types of NMN supplements may cause different side effects. If you find that you're having a hard time with capsules, you could try other forms of NMN supplements.
Capsules
NMN capsules are one of the most common ways to take NMN, as they're convenient and come in pre-measured doses. However, they can sometimes cause nausea or digestive discomfort, especially if taken on an empty stomach. Taking them with food usually helps.
Gummies
NMN gummies aren't as common, but they're a nice treat if you can find them. It combines NMN in a chewy candy formula that makes taking pre-measured doses of NMN easier on the stomach.
Powder
With NMN powder, you get more flexibility in dosing, but it can sometimes cause bloating or stomach discomfort, especially if not mixed well or taken without food. Make sure to follow instructions and mix the powder thoroughly.
Sublingual Tablets
Sublingual tablets dissolve under your tongue for faster absorption. Some people might experience mouth irritation or a slight burning sensation, but these tablets bypass the digestive system, which can help avoid stomach issues.
Sublingual tablets aren't as widely available as other forms of NMN as there's an argument for the compound not being small enough to absorb under the tongue, which is why liposomal NMN and other NAD precursors such as NR (nicotinamide riboside) or niacin (vitamin B) might be more desirable forms for supporting NAD+ levels in the body. You are likely to experience less side effects from precursors or liposomal supplements because of their absorption rate.
Sublingual Drops
Sublingual NMN drops liquid supplements are absorbed under the tongue, allowing faster delivery into the bloodstream than capsules or powder.
Some people have reported feeling a mild burning or tingling under the tongue, mainly if the product contains alcohol. This usually fades, but switching forms can help if it persists. Another common complaint is that the drops may have a strong taste, which can be diluted with water if needed.
Are There Any Side Effects of NMN + Resveratrol?
NMN and resveratrol are often taken together because they are believed to support cellular health through different but complementary pathways.
While both supplements are usually safe, some people might experience mild side effects like headaches, nausea, or digestive issues if they take too much. It’s best to start with a lower dose and see how your body reacts before increasing it.
So, Is NMN Generally Safe?
At the end of the day, as long as you're purchasing NMN supplements from a reputable brand that's transparent about what goes into their supplements, they are considered safe. But, like with any supplements, there's still a small risk of side effects like headaches, stomach upset, and nausea.
While not well documented in scientific literature, some people also report feeling tired or experiencing mood changes when they stop taking NMN, which could be due to their NAD+ levels returning to normal. Before starting NMN, especially if you combine it with resveratrol or other supplements, it’s always smart to check with a healthcare provider.
