Fish Oil and taking fiber

(Rob) #1

Hi all,
I take fiber at least twice a day. Generic metamucil to keep things running normal.
I also take fish oil. And it occurred to me that since I take them near the same time, have I been short-circuiting the fish oil with the fiber? Could the fiber be absorbing the fish oil to the point it doesn’t get digested?

Any thoughts/opinions greatly appreciated,

(Doug) #2

I don’t think the fiber changes anything, there. The chemicals that your body uses to digest the oil go all through, in and around the fiber; the oil can’t ‘hide’ anywhere.

Within the whole spectrum of drugs/laxatives/neutraceutical products (like fish oil) there are no known interactions between psyllium fiber and fish oil, so, here, I think it’s all good.

(Rob) #3

Thanks for the info. I thought the fiber was absorbing the oil and wasn’t being digested.



Hey Rob. I reckon it’s a good idea to get those Omega 3 fatty acids (fish oil being a concentrated form) in your diet. So fantastic for brain health and to help regulate body inflammation. Thanks for posting your question. My understanding aligns with @OldDoug, Doug on the fibre not being a shield to fat absorption. That said. And I think you may have some gut instinct here. How about separating the doses, if possible and see how you feel? It would be an interesting observation to make.

For my Omega 3’s, I eat grass-fed red meat and add some tinned mackerel or sardines to the meal as I like the seafood flavours. I really do love surf’n’turf!

(Rob) #5

Hi FrankoBear, I already separate the doses - take 2000mg in the morning and 1000mg at night. I remember reading somewhere that the standard dose of 2000mg was too light and this feels just right. The reason I take it as a supplement is that I can’t stand oily fish - I hate salmon, sardines etc. When I eat fish I tend to eat whitefish - cod, flounder, haddock etc. So to make up for it I take supps.

Also, I’m not in a financial place where I can routinely get things like grass-fed beef.



Interesting question.I do not believe there is any evidence to suggest that with the addition of fibre you are short circuiting the absorbion on the fish oil. I would run a test. Why not get your fibre from real food vs a supplement?

(Rob) #7

Why do I take fiber this way? Long history of doing LC and constipation. Taking fiber as a sup is fast, easy and works.

(Joey) #8

Interesting outcome. I’ve read that responses to fiber are all over the map.

For constipation, my wife and I find that magnesium citrate does the trick while also serving as a muscle relaxant - keeping muscle spasms/cramps at bay.

(Bob M) #9

The responses are all over the map.

For me, fiber CAUSES constipation. I avoid fiber because of that. For instance, I can have a salad every once in a while. But if I have a lot of salads, say I’m on vacation and getting salads with my meals instead of french fries, I will have horrible constipation, IBS, etc. Going back to a low fiber diet cures all of that.

I’ve always wondered why some people can handle fiber and others cannot.

(KM) #10

Lol. I’ve sometimes imagined I could eat grass and bark with no problem if I had no other choice. But I don’t seem to have a problem with digestion if I’m entirely missing fiber, either. :woman_shrugging:


It’s pretty simple; you probably lack certain gut bacteria that help digest fiber. Fiber can also act as a prebiotic (food source) to help the good bacterium proliferate.

(Rob) #12

One other side effect of taking fiber as a supplement - that it really makes you feel full. Much easier to stay disciplined.

And one more thing - it is very easy to measure how much fiber you are getting.


(Bob M) #13

@ffskier You might not realize this, but I was on keto back when the whole “potato starch” and “probiotics” craze was going around. Took tons of potato starch (and other “prebiotics”) and many, many different varieties of probiotics. The end result? No benefits I could see, and only detriments. At least a year doing this. Have data back from then showing I could stay in ketosis while eating potato starch.

@Steelerfan2024 That is what people say, that fiber causes people to feel fuller. I see no evidence of that though. Here’s one study for instance:

This is an illustration of what happens in this area. In epidemiological (epi) studies, there’s a correlation between people who (say they) eat more fiber and lower body weight (or any number of other potential benefits). But when they actually do an RCT (randomized controlled trial), fiber pretty much fails most times.

For anyone who feels better eating fiber, then do so. Don’t let me stop you. But don’t try to apply the perceived benefits you get to other (like me) who don’t get the same benefits and in fact get detriments instead.

(KM) #14

Back in the day I would actually mix psyllium husk into ice cold vegetable juice as an afternoon snack. A Gloppy Mary, so to speak. It did fill me up and keep me from snacking til dinner time, which was useful. I don’t think it was necessary or especially beneficial beyond that, but it probably wasn’t a terrible protocol either.


When you refer to probiotics, do you specifically mean probiotic supplement pills? Or foods that contain probiotics? With potato starch, were you taking the powder? Or eating a cold potato, and in the gut it acts like a resistant starch to feed the gut biome?
How did you determine which probiotics were deficient, and at what dose level did you self-administer them?

There is a performance product called UCAN Generation that is primarily potatoe starch that gives you approx 20 grams of carbs per serving with no spike in blood sugar. I first used this product 10+ years ago while in Keto and bike racing, but still needing the carb rocket fuel when the race intensity increased. I still use it but do not race as much as I used to.


I get it. But why not address the problem of constipation? Why is your pumbling slow? Or could you be missing something in your diet? How do you determine how much fiber to take and in what dose? Are you not concerned about taking a supplement for the long term? I ask because I know of somebody who did take regular fiber supplements every day and had allergic reactions, yet did not recognize it until he eventually had an anaphylaxis reaction and was rushed to the hospital, where it was discovered the cause was the fiber supplement.


I always thought (still do) that the “filling fiber” is simply individual. Some people feel full from it while some of us not at all. Fiber never ever made me more full or satiated or anything or had any benefits I could perceive. But I believe it works for others.

(Geoffrey) #18

Same same.

(Rob) #19

Any time I do low carb, I get constipated. Happened 20 years ago when I was on atkins, happens now. I determine the dose by trial and error. Taking twice a day works wonders. I was thinking of going to 3 a day - like the directions say - but haven’t gotten around to it yet. I’ve never had any issues with fiber.

(Bacon is a many-splendoured thing) #20

The cumulative experience on these forums is that some people absolutely need fibre, others find that fibre exacerbates their IBS, Crohn’s disease, etc., and the vast majority are fine with or without fibre.

Myself, I find that getting enough fat and staying within the right range of salt intake eliminates (so to speak!) my need for fibre.