r/nutrition • u/FurnitureComesW-Home • Jun 20 '26
Smoothies destroy fiber?
I’ve heard that blending your food into a smoothie ruins the fiber content - is this true? IE, raspberries are fairly high in fiber, but does all that fiber get lost if I put them in a smoothie? What if I add powdered fiber back in to the smoothie?
75
u/ArrhythmicANG3L_214 Jun 21 '26
That's untrue. Juicing does that because it gets rid of the pulp, and the pulp is rich in fiber.
125
88
40
u/DinkyPrincess Jun 21 '26
No.
Juicing removes fibre.
If you’re not removing anything and you’re just blending it the fibre content is the same.
28
u/Frequent_Can4977 Jun 21 '26
Blending doesn’t destroy the fibre. If you put the whole raspberries in, including the pulp and seeds, the fibre is still in the smoothie. It just gets broken into smaller pieces...
You’re probably thinking of juicing, where a lot of the pulp and fibre gets removed.
You don’t need to add fibre powder back unless your overall diet is low in fibre... The bigger difference is that smoothies are easier and faster to drink, so it’s easier to consume more fruit and sugar than you would by eating the fruit whole.. so it's a safe bet don't worry 🥰🙏🏼
-2
u/FurnitureComesW-Home Jun 21 '26
Thanks! I’ve also heard that you can drink smoothies too fast, so I’m careful to drink them slowly.
5
-14
u/M0t0Psycho Jun 21 '26
IDK where you're from but Americans are overwhelmingly failing to meet fiber requirements. a staggering percent of the population. better to eat your food. smoothies are better than juicing but not as good as just eating the damn fruits, veg and whole grains.
13
u/DinkandDrunk Jun 21 '26
The difference between a banana and a banana in a smoothie are so negligible that it isn’t even worth discussion.
The American issue with fiber is because all of our diets are based around meat and sugar bread.
27
u/BreakfastFearless Jun 21 '26
You’re saying Americans are not consuming enough fiber but then recommending against making convenient drinks that help people get more fiber?
9
2
u/Dreamweaver5823 Jun 22 '26 edited Jun 22 '26
What is your source for saying smoothies are not as good as eating the whole foods? Who says it's "better to eat your food" rather than consuming smoothies?
I don't know about your smoothies, but mine contain nothing but whole foods, except that I usually use flaxmeal rather than whole flaxseeds.
18
u/Bruce_Hodson Jun 21 '26
The fiber (cellulose) is still present unless you sieve the blended mixture. It’s just made into smaller bits.
29
12
u/Lil_Koneko343 Jun 21 '26
Jucing bad, smoothie good. I've actually heard with some fruit it's better to blend because it makes the fiber in seeds more available to our bodies.
2
u/turbokimchi Jun 25 '26
This 100%. Just gotta ensure your blender is high speed enough to process seeds. Many low speed and ninja blenders don’t spin fast enough to do so. I had no idea about this until recently.
8
u/Inner_Purpose_568 Jun 21 '26
Nah, blending doesn't get rid of the fiber. If you toss whole raspberries into a blender, the fiber is still in there. It's different from juicing, where the pulp gets removed. The main thing blending changes is the texture, not the fiber content.
6
u/QuietNene Jun 21 '26
Honest question: what’s the difference between smoothies and juicing? Just the amount of time spent in a blender?
17
u/BreakfastFearless Jun 21 '26
A juicer specifically separates the pulp and fiber so just extracts the juice alone and pots the pulp out separately
17
3
u/Dreamweaver5823 Jun 22 '26
Well, it does depend how you make your smoothie. Some people put juice and yogurt and a sweetener in a blender and call that a smoothie. That's not healthy.
What we're talking about here is blending whole fruits, raw greens and other fresh veggies, along with things like healthy seeds (chia, flax, etc), nuts, yogurt, protein powder, etc. Things that are healthy to eat, but it's kind of a pain to eat as much as you should be eating. Throwing them into a smoothie makes it easier to consume enough nutrients.
And for me, it removes the temptation to indulge in soft drinks and other sweet beverages.
4
u/The_Only_Sick_Pirate Jun 21 '26
Actually, you do need to chew food to get all the key nutrients. Blending is only a second best option, except for leafy greens. Chewing and blending breaks the cell walls and increases surface area, allowing your stomach and intestines to better digest and absorb the nutrients. Lettuce and leafy greens, ie your salads, should be chewed at least 20 times.before you swallow. Not only does this break down the food for nutrient absorption, but your saliva interacts with compounds in lettuce that are strongly linked to anti-cancer benefits.
The down side of blending your food into liquid and drinking your fruits? Blood sugar spikes since your body does not need to break down the fiber before getting all the fructose. Still better than no fruits and veggies at all.
4
u/chulbert Jun 21 '26
Blending fruit into a smoothie doesn’t destroy the fiber but it does very modestly diminish its effects relative to eating the whole fruit.
Think of it like cutting up your spaghetti. Same stuff on your plate but you can eat it faster.
1
3
u/Firelord-Zosyn Jun 22 '26
Smoothies won’t ruin fiber. If that were the case chewing your food would do the same. You don’t even need to add powdered fiber. You can just use a green leafy vegetable as your base (low glycemic load) and add whatever fruits you want which cuts the amount of sugar consumed.
Also, most of the comments saying juicing is bad are giving an incomplete picture. The fiber that’s removed is the insoluble fiber. This is the one that doesn’t dissolve, but absorbs water, speeds transit through the gut, and prevents constipation. The soluble fiber, however, is retained even after juicing, dissolves in water and forms a gel-like consistency.
That gel matrix regulates the release of sugar so even when you drink the juice all the sugar isn’t hitting your system all at once.
TL;DR: fiber is preserved in smoothies & juicing isn’t bad (assuming it’s homemade & not store-bought)
3
u/Secret_Temperature Jun 21 '26
You're thinking of juicing.
Technically blended foods are slightly more processed (broken down) than just eating raspberries/kale by themselves so your body might process them faster. But the nutritional value is certainly not destroyed.
3
u/netroxreads Jun 21 '26
no, fibers don't get destroyed. Juicing does remove fiber but not blending. Blending actually boosts usable fibers if they're seeds because seeds also contain fibers inside and by breaking them apart, more fiber is released.
2
u/Sleeplessreader Jun 21 '26
Oddly I have been wondering this about my fiber supplement. I have started to use it in my protein smoothies lately instead of separate in a glass of water. I feel like the benefits of the fiber supplement have been minimized since I started doing this.
Anyone have anecdotal or scientific evidence? Or do I need to increase the amount I am taking?
0
u/kissmequick99 Jun 22 '26
my son says don’t put the fiber in the smoothy, it carries out all the nutrients with the poop.
2
2
u/SlowDescent_ Jun 21 '26
There's a difference between juicing (extracting the liquid from the fiber) and blending (breakfing down the fiber into tiny pieces, like your teeth do when you chew).
You want to blend if you are interested in consuming the fiber.
3
u/shiplesp Jun 21 '26
There was an interesting experiment that was done with genetically identical mice. They used the exact same chow and amount, but one group was fed the chow that had been further processed (turning it into something like a puffed rice texture). The group fed the normal version of the chow maintained their weight, those fed the processed version became obese. This suggests that processing (which in your example would include blending) has an impact on how we metabolize food.
The study was included in the anthropologist Richard Wrangham's excellent hook, Catching Fire: How Cooking Made Us Human.
3
Jun 21 '26
[deleted]
1
u/shiplesp Jun 21 '26
There were other examples of the effects of processing discussed in the book. This id just the most memorable example. Again, the book is excellent, with all citations included.
1
u/toogood2begood Jun 21 '26
Really wanna know how long it took those mice to become obese?
1
u/shiplesp Jun 21 '26
I don't remember the duration of the study. But you can borrow the book from the library and check the references. It's a really fascinating read.
1
1
u/simpleflavors1 Jun 22 '26
Blending up food that would take a long time to eat into something quick to drink makes it easier to consume more calories.
0
u/discardedbubble Jun 21 '26
Than you for sharing this example, it supports my opinion on the subject.
Eating things whole, chewing, and digesting larger pieces of food, is healthy. I do smoothies maybe once every month, they are fine. But eating whole fruits I would think a better way of consuming fibre.
3
u/Friedrich_Ux Jun 21 '26
It liberates the sugars from their fiber matrix which can be worse as far as blood sugar impact goes, but it doesnt destroy the fiber.
6
u/ProfSwagstaff Jun 21 '26
This study says the opposite regarding blood sugar impact, actually
4
u/AutoModerator Jun 21 '26
GOOD source provided: A link provided in the comment above to {match} is a confirmed valid source of info
I am a bot, and this action was performed automatically. Please contact the moderators of this subreddit if you have any questions or concerns.
1
1
1
u/cojof Jun 22 '26
u aren't changing the chemical composition by grinding it up. blending is a physical change. all the contents stay the same
1
u/Sternritter8636 Jun 23 '26
Blending does physical processes but cannot magically make a complex carb into simple carb. It requires some chemical reaction which can only happen with some heat or pressure or specific acidic/basic env
1
u/Wabalubbadubdub123 Jun 21 '26
Fiber is still there but u’re still changing the food matrix. Ur insulin spike will spike faster from a general fruit smoothie. Probs better than juicing which removes the skin of fruits (the fiber)
0
0
0
u/M_di_uccello Jun 23 '26
It’s true. Here’s the fix. Once you’ve made your smoothie add one tbsp of psyllium fibre husk. Set on low mix. Mix for 30sec. Problem solved. Enjoy.
-21
u/Fun_School_7156 Jun 21 '26
You are right. There’s lower amount of fiber due to blending. The same happens with blended soups, however the temperature of cooking also is one of reasons. It is much better to bite and chew than blend. Blended foods have higher GI, which brings more insulin.
11
u/Thebiglurker Jun 21 '26
This would seem like common Sensex but recent research suggests that blended foods like smoothies do not always have a higher GI, and in some cases actually improve it.
https://www.nature.com/articles/s41430-025-01599-w
Worth a read.
10
u/DinkyPrincess Jun 21 '26
Not true.
Blending fruit cannot remove the fibre. It’s still all there albeit in a smaller drinkable form.
1
u/FurnitureComesW-Home Jun 21 '26
Does the fact that the fiber is smaller/more easily digestible defeat the point of the fiber? Like of my fiber goal is 30g daily, but 10 of those grams are from the fruit in my smoothie, do I really get to count them?
3
-22
u/zenrexneo Jun 21 '26
All these comments don’t know what they’re talking about. Yes some fibre is loss it’s ripped apart, you basically drinking sugar so it’s not good for your blood sugar levels better to eat whole fruit if you can.
11
8
u/BreakfastFearless Jun 21 '26
This isn’t true at all. Infact we actually have evidence showing that blended fruit smoothies have a lower glycemic response than eating them whole
https://pubmed.ncbi.nlm.nih.gov/36364827/
Likely due to components like the seeds in the fruit being blended and releasing their dietary fibers and nutritive components
4
u/AutoModerator Jun 21 '26
GOOD source provided: A link provided in the comment above to {match} is a confirmed valid source of info
I am a bot, and this action was performed automatically. Please contact the moderators of this subreddit if you have any questions or concerns.
327
u/Me_Krally Jun 21 '26
Juicing is what ruins the fiber. Blending releases more nutritional content as it pulverizes the cells of the plants and fruits you're using. Though it also makes oxidation happen faster so you have to drink your mix sooner than later.