Did you know vitamin B3 protects against skin cancer?

Living in sun-soaked Australia, skin cancer is real. Yet few of us know that vitamin B3 has been shown, by Sydney University, to reduce some skin cancers by up to 30%. This feels like something we should know alongside “slip, slop, slap.”

Sadly, the message has not been shared widely because public health messages must be simple and clear and vitamin B3 is a little bit complicated, as you will see below.

Where did it all start?

It all started in 1997 when a researcher at Sydney Uni decided to see if vitamin B3 helped with UV damage to the skin of mice. Whoever thought of doing that?! (read the study here) The results were promising. Skin tumors dropped from 70% to 40%.

A few smaller studies paved the way for a large clinical trial in humans in 2015 called ONTRACT (here).

In this study, 386 people who had had two or more basal cell carcinomas (BCC) or squamous cell carcinomas (SCC) skin cancers in the last 5 years took either 1000mg of the 'nicotinamide' form of vitamin B3 each day, or nothing, for 12 months.

The results were impressive. The group taking the nicotinamide had 30% less chance of SCCs and 20% less chance of BCCs compared to the group taking the placebo.

In real numbers there were 336 new BCC/SCC in the vitamin group and 463 in the placebo group who were taking nothing. Plus, pre cancerous spots reduced by 11% to 20%.

Note: The research was only on non-melanoma skin cancers known as BCC and SCCs.

How could the humble vitamin B3 do this?

Explaining it as simply as I can...

Skin cancer happens when UV rays damage the skin’s DNA. The DNA goes rogue and allow bad stuff to grow. Normally, cells have energy to fight the bad stuff and stop it growing.

When we are young we have lots of energy to stop the growth and tidy things up. But as we get older we have less energy so the bad staff doesn’t repair as well. This is why skin cancers appear as we get older.

Vitamin B3, or more specifically the nicotinamide version of B3, is a precursor to something which gives cells an energy boost. (The thing is NAD+ which you may have heard about in longevity circles). By giving damaged cells more energy they are better able to fix DNA damage and stop bad stuff - or cancers - from growing.

Why is vitamin B3 complicated? What do you mean by the nicotinamide version of B3?

Vitamin B3 is not as simple as vitamin B3. There are lots of different types and their names are frustratingly similar.

The one we care about for skin cancer – that boosts the energy to cells – is called nicotinamide (or sometimes niacinamide or NAM). For this article, I’ll stick to nicotinamide.  

The other one we hear about is niacin. Also known as nicotinic acid. This is what we see on food labels (which, FYI inaccurately bundle all vitamin B3 under the name ‘niacin’). Niacin is useful for heart health because it relaxes blood vessels. Niacin is also a bit tricky, because at high doses, it can cause something called flushing where someone’s skin gets warm red and itchy. This happens because of the rapid relaxation of the blood vessels. For most people this isn’t serious, but it is unpleasant and can last around 30 minutes. (There are other forms of B3, where the niacin is attached to an inositol backbone to avoid flushing… but let’s keep it simple).

The other types of vitamin B3 that are bandied around in longevity circles are nicotinamide riboside (NR) and nicotinamide mononucleotide (NMN). I won’t bore you with the details.

Suffice to say there are a lot of ‘nico’ and 'NADs' that make it confusing.

This sounds great. Can't I get this from food?

People in the ONTRAC study took 1000mg of nicotinamide each day, with two doses of 500mg each.

To get this amount from food would be near impossible.

The average Australian diet provides around 20-40mg per day.

The minimum recommended amount per day is 15mg per day.

Compared to 1000mg these amounts don't even touch the surface.

Animal foods tend to provide more nicotinamide than plant foods and animal foods have tryptophan which helps the body to self-make some nicotinamide.

Here is an idea of the amounts you might get from some of the heavier hitters in the B3 department:

• A medium tuna steak - 30mg

• One small chicken breast - 22mg

• One chicken liver - 12mg

• One cup portabella mushrooms - 5mg

• Half cup cooked brown rice - 2mg

• Processed foods - milling of grain strips out the B3 and so food companies fortify products with B3. You could probably get around 8mg each day relatively easily eatin processed cereals, protein bars etc.

For historians, the 15mg minimum requirement is the amount needed to prevent overt deficiency which causes pellagra. Pellagra is when high-energy needing cells in the skin, guts and brain suffer causing symptoms of the ‘4Ds': diarrhea, dementia, dermatitis and death. Pellagra was first recognised as a nutrient deficiency in the early 1900s when pellagra hit communities eating diets high in maize (think of ground corn). Maize has low vitamin B3 and what it has is hard to absorb.

Whatever way you look at it, the overall amounts of B3 from food are relatively pathetic if you are targeting a daily 1000mg.  

Does this mean we should supplement?

If you've previously had a non-melanoma skin cancer, it's definitely worth talking to your doctor about whether nicotinamide is appropriate for you. In this case you would be looking at taking 500 mg of nicotinamide twice a day - morning and evening, with or without food - as they did in ONTRACT.

The product used in the trial was a Blackmores product, which I understand is now marketed as Insolar and cost around 20-30c per 500 mg tablet.

A few words of warning when choosing a nicotinamide supplement:

• Don't accidentally get niacin - if you tried to achieve 1000mg with niacin it would be very very dangerous. Your would almost certainly get the unpleasant flushing (which happens at doses of around 50mg or more) and you would probably be very very sick. Don't do this!

• Don't accidentally get 'nicotinamide riboside chloride' - the name is remarkably similar and it is not the right one - this is one of those longevity ones.

• Don't think your multivitamin or B complex vitamin will tick the boxes - you want to get the right dose to ensure the benefits. The amount of nicotinamide in the B complex multivitamins I look at ranged from 25 mg in Herbs of Gold to 220 mg in Metagenics.

• Don't accidentally overdose on other vitamins from taking lots of different supplements. This is a real and overlooked risk. B vitamins are often added to supplement concoctions as 'harmless extras'. Yet the combined dose can be problematic. In 2025, the risk of overdosing on vitamin B6 hit the headlines when GPs were warned excess vitamin B6 can cause nerve damage.

What if you haven't yet had a skin cancer?

If you haven't yet had a skin cancer then there is not really a good case for taking a nicotinamide supplement. The research has not yet looked at whether this would be beneficial and we can't assume it would be (although the mechanism by which is works makes sense).

My personal view is that we should all be making sure our day to day diet covers the basics for supporting cellular energy.

After a day at the beach, we're surrounded by moisturisers to help repair and soothe the skin. No one thinks about eating well to support the body's internal cell repair systems.

These internal repair systems are very real and totally forgotten!

Your body has incredible clean up systems. Yet 30% of Australians in 2023 did not achieve the minimum intake of one of the key nutrients (zinc) needed to power these systems! (ABS statistics)

Plus food itself has incredible cell repair medicines in them. Yet 90-95% of Australians in 2023 did not achieve the minimum recommended amount of these 'repair medicine' foods! (ABS statistics). Teenage boys lead the charge in this department.

This, quite frankly, is shocking for a country that is swimming in sun and skin cancers.

Get in touch

If you'd like help to get the basics right, to review your supplement cupboard, or to figure out how to take the right dose of nicotinamide to protect against future BCC or SCCs, then please get in touch to see if I can help you.

Book an initial session here or book a 15-minute chat to talk through what you're looking for and whether I can help.

Sessions are available Monday to Thursday, either online, in Rose Bay or Sydney CBD (near the Rocks/Circular Quay).