Supplement Stack: Dennis Mangan

By on January 8, 2023

This week we got a chance to sit down and discuss supplements with Dennis Mangan (also known as P.D Mangan) of Rogue Health and Fitness. Dennis is an expert on men’s health, longevity, strength exercises and virility, and has written some pretty awesome books on all he knows. His latest book Muscle Up is out on Amazon and it tells us how ‘strength training beats obesity, cancer and heart diseases, and why everyone should be doing it’.

We had a great talk with Dennis on his supplement stack and why Lithium is the most surprising vitamin he takes.


1.) What is the reason you’re taking supplements?

I’ve been taking some supplements, like multivitamins, for a long time. What got me going in earnest was having chronic fatigue syndrome. None of the many doctors I’d seen for it had much of a clue as to what was wrong with me and how to fix it, so I started researching myself. I came across many articles about various supplements that I thought seemed to have a decent chance of improving my health, so I started getting them and taking them. Eventually and with the help of supplements I completely overcame chronic fatigue.

As for why I take supplements now, I want to have optimal health and I believe that a number of different supplements will help me in that objective. The nutrients that we need are not all available just from food, and even when they are, considerable work may be required to get them. For instance, omega-3 fatty acids: if you eat fatty fish several times a week you can get all you need; but I don’t, and don’t really care to, so I take a fish oil supplement. Vitamin D is another good example: adequate vitamin D intake requires plenty of sun exposure, and in the winter in many places even that won’t do. So I take a vitamin D capsule.

Other supplements simply can’t be had from food in the amounts necessary for physiological effect, resveratrol and curcumin for example. Others not at all, like aspirin and hydroxycitrate.


2.) What are the current supplements you’re taking?

Maybe I should just list them here. I don’t take all of these daily, but do take them regularly.

  • Resveratrol
  • Curcumin
  • Aspirin
  • Vitamin D
  • Magnesium
  • Zinc
  • Selenium
  • L-citrulline
  • Whey protein
  • Creatine
  • Cod liver oil
  • Vitamin K
  • Theanine
  • Lithium orotate
  • Hydroxycitrate
  • Nicotinamide (vitamin B3)

Some supplements are in my rotation, but I usually take them only when I think they’re needed, such as if I’m overly fatigued or ill. These are:

Vitamin C


3.) What’s the most recent supplement you’ve recently added? Why? Have you noticed a difference since you added it?

I added l-citrulline recently. I take up to 1500 mg before a workout, and I do feel I’ve noticed a difference. Citrulline has been shown to increase exercise capacity through increased NO (nitric oxide), and I believe my workouts are going better. My muscles also have more vascularity now and this could be due in part to citrulline.


4.) Are there any supplements that you used to take but you stopped? Why did you remove it? Did you notice an improvement after removing it?

I used to take probiotics regularly, back when I was ill, but don’t anymore just because I don’t think I need to. That said, they can be very helpful in many conditions (such as chronic fatigue), so I don’t disdain their use.

I’ve tried DHEA at several different times, but it pretty reliably gives me acne, so I stopped.

There are certain supplements that probably very few people should take, calcium being a notable example. Epidemiological evidence shows an increased mortality rate in those taking calcium, probably by exacerbating atherosclerosis.


5.) What’s the most unexpected or surprising or least-common supplement you’re currently taking? Why are you taking this one?

Maybe lithium. People are surprised at this supplement and think it’s something for bipolar disorder. The supplement dose is hundreds- or thousands-fold less than the pharmaceutical dose. Lithium appears to be a required nutrient – “appears” because little research has been done on it, but lab animals deprived of it do not do well at all. It increases lifespan in C. elegans, the standard lab animal (a worm) used for life extension experiments, and in humans, more lithium in drinking water is associated with longer life. The amount required for good health appears to be about 1 mg a day. I take a 5 mg supplement two to three times a week.

Most of the supplements I take have no psychotropic effects, but one, theanine, does. When I started taking it I was genuinely surprised that it really lowers anxiety and creates a sense of focus.


6.) Are there any supplements in your stack that you’re considering eliminating? Which one? Why? Do you think you will?

Not long ago I bought some casein protein to add on workout days, as some evidence shows that it could be better for muscle growth than whey. But it’s also the protein that most increases IGF-1, a growth factor but which also promotes aging. I haven’t had noticeable results since adding it, and that and the fact that it may be pro-aging inclines me to drop it.

Resveratrol is an interesting case. Most of the good results seem to come from animals and humans with damaged metabolism – obese, high blood glucose, that sort of thing. It may have little effect on healthy humans and animals, although it extends life in C. elegans. Since I don’t have any metabolic issues that I know of, I’m not sure how much it helps me. I certainly don’t think it does me harm, and I bought a bulk supply, so I continue taking it.


7.) Are there any supplements you’re considering adding to your stack? Which one? Why? Do you think you will?

For awhile there not long ago I was taking glycine, an amino acid. At least one study suggests that it could have a strong anti-aging effect (by mimicking methionine restriction and by normalizing old mitochondria), and it seems I felt better when taking it. It also, in conjunction with n-acetylcysteine, can raise glutathione levels in older people and thus combats oxidative stress, a main component of aging. It also promotes sleep, although I never felt an effect on my own sleep. I went through my entire supply of glycine, which is easy to do as a dose is 2 to 3 grams. So, thanks for reminding me, I should probably get some more.

About Author


We love hearing from fellow supplement freaks - email us at



We're open to interview anyone with an interesting supplement stack. Email us at and tell us one reason why your stack is interesting.