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> "if you put some berries in a blender and drink it, you're getting entirely different nutrition from eating the berries raw!" That second one is a bit of a strawman, but it shows how absurd claims that crushing or grinding foods ruins the nutrition sound.

Well, for many foods this is 100% true. For instance, it's not the same eating raw garlic, than freshly smashed garlic (<10mins), than garlic smashed 20 minutes ago... because allicin (main active compound of garlic) is unstable and quickly degrades into another compounds...

https://en.wikipedia.org/wiki/Allicin

Yeah, I was gonna say-- pureeing berries severely impacts dietary fiber, which in turn impacts glycemic index, since your body no longer has to work around nearly as much cellulose to get to the sugar. It's a physical process that has an impact on a chemical process. And of course you chew your food, but you can't chew anything nearly so fine as your blender does.

Here's a more concrete analogy-- sawdust is highly flammable. Many times more so than regular old wood. Why? Better oxygenation, higher surface area, lower per-unit thermal mass (which means less energy required to get a particular chip of wood to its combustion point).

> Yeah, I was gonna say-- pureeing berries severely impacts dietary fiber, which in turn impacts glycemic index, since your body no longer has to work around nearly as much cellulose to get to the sugar.

When I first got my Vitamix, I did some cursory web "research" which seemed to imply that blending made no substantive difference in nutritional value of fruits. Do you have a citation for this conclusion?

The general rule of thumb is cooked digests easier than raw, blended easier than cooked, juiced easiest of all. Think of it as automating preexisting parts of the natural digestive cycle-- you chew your food physically for a reason, obviously, starting in the mouth and continuing in the stomach. Cooking denatures protein. Pureeing similarly breaks down dietary fiber into smaller, more digestable chunks. Everything is still there (excepting volatile organic compounds that degrade once exposed to air, etc), it's a physical process, not chemical. But physical transformations have indisputable effects on chemical reactions. That's not controversial.

(Caveat: nutritional science is very much in the wild wild west days. It's a jungle out there, even in peer-reviewed research.)

https://www.ncbi.nlm.nih.gov/pubmed/3046297

He doesn't have a citation because he's wrong.

But I do, sunshine. Do you?

Your citation is about starch. A better citation in support of your assertion https://www.ncbi.nlm.nih.gov/pubmed/71495

But does that change the nutritional value of garlic (as opposed to changing just the taste)?

If you lose allicin you lose some nice properties (antimicrobial, antiinflammatory, etc):

https://www.ncbi.nlm.nih.gov/pubmed/10594976

But those properties may not be relevant to you when consuming garlic anyway. The vast majority of such studies are showing the properties in isolation (petri-dish).

People love to extrapolate that to "garlic prevents colds", but it doesn't follow. I'm not going to pay to read the full article in this case but you at least have to be careful about this.

> But those properties may not be relevant to you when consuming garlic anyway.

Many of this properties are well known (not so well understood). I posted a random quick example, but there are also studies in vivo (rodent models and humans).

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4103721/

My point was that you have to be careful in general. In the specific case of garlic, I don't draw the conclusion from your second link that it is "well known". There are some promising results for some of the individual diseases, but there are also many caveats. The conclusion states:

"Although it is shown that garlic may have a significant clinical potential either in their own right or as adjuvant therapy in different disorders, however, due to some issues, such as methodological inadequacies, small sample sizes, lack of information regarding dose rationale, variation between efficacy and effectiveness trials, the absence of a placebo comparator, or lack of control groups more standard experiments and researches are needed to confirm the beneficial effect of garlic in various diseases."

> I don't draw the conclusion from your second link that it is "well known".

Then it must be a cultural thing... =) If you read the first sentence in the abstract you can read: "Throughout history, many different cultures have recognized the potential use of garlic for prevention and treatment of different diseases.".

Here in the Mediterranean, garlic is known to be really healthy (along with red wine and olive oil). Many people eat garlic in the morning just for the health benefits, and we even have (famous?) smashed garlic dishes: https://en.wikipedia.org/wiki/Aioli

> My point was that you have to be careful in general.

Agree. Sometimes more context/evidence is required. My point is that the bioavailability of compounds in food might differ if the food is presented in raw or elaborated/processed form.

The first sentence is setting the scene, not confirming the hypothesis. If things being "known" by cultural history was sufficient, we wouldn't need to do science. In reality, a good proportion of "known" things are wrong or the very minimum more subtle than expected.

It is also "known" that being physically cold causes colds (Mediterraneans are especially paranoid about this in my experience). The majority of studies show this to be either untrue or borderline.

I do agree that there is clear potential for chopping food to affect it's nutritional value. I would expect chopping alone to be of minimal impact in most cases if no other evidence was available. Elaborate processing is rather different.

It's almost as though breaking down the cell walls of plant material exposes various molecules to oxygen and other compound in air resulting in the possibility for chemical change than would exist it the material was consumed directly.

Unless you swallow your food whole I imagine that your teeth might break down cell walls too.

Aren't you severely grinding it with your teeth, saliva, and gastric acids anyway?

(Honestly asking, I have no idea.)

Correct. Freshly blended food is also no issue.

The first issue is that you don’t immediately consume it after blending, but wait a few minutes or hours.

The second issue is that the grinding with teeth requires you to spend energy, which reduces the energy you gain from the food.

Right, but teeth are natural and a mortar and pestle are not /s

How does rushing it into an acid bath preserve it?

The goal isn't to preserve it forever, the goal is to preserve it long enough to get to the bacteria which can make use of it.

Antimicrobial food would be bad for you as it would harm digestion.

Not quite true. Antimicrobial doesn't mean quite what you think; it means anti-some-microbes. Honey, for instance, has several antimicrobial or antibiotic aspects. Some honey is so because enzymes in it produce hydrogen peroxide, while other honey is so for different reasons, not fully understood. If you feed mice a lot of honey, their intestinal flora rebalance -- in one study, for instance, feeding mice honey as a food supplement increased their bifidobacteria and lactobacilli counts. This is actually probably good for digestion.

Feed mice a new diet of any kind and their gut will rebalance.

We cannot assume that the environment is innocuous. Our atmosphere is full of nitrogen, oxygen and other chemical compounds able to produce a reaction and modify molecules in any food.

https://en.wikipedia.org/wiki/Active_ingredient

"An active ingredient (AI) is the ingredient in a pharmaceutical drug that is biologically active. " Does it also reduce the amount of rainbows and unicorns? Your own wikipedia link does not say eating garlic is helpful to humans.

Sorry, I meant "active compound"...

> Your own wikipedia link does not say eating garlic is helpful to humans.

As you may know, you shouldn't look in wikipedia for that kind of information... here you go:

"Recent studies support the effects of garlic and its extracts in a wide range of applications. These studies raised the possibility of revival of garlic therapeutic values in different diseases. Different compounds in garlic are thought to reduce the risk for cardiovascular diseases, have anti-tumor and anti-microbial effects, and show benefit on high blood glucose concentration."

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4103721/

But the point here is (in case you missed it): eating smashed food != eating raw food

http://examine.com/supplements/garlic/#summary1-0

I thought the biggest problem with blending stuff is the quantity I'll be having compared to having just one unit of something. For example, I wouldn't eat 3 oranges in a row but I would definitely drink them if blended.

Mashed potatoes is a big one for me. Would never eat 5 boiled potatoes, but if I make mashed potatoes out of them I'll happily eat that much and quite possible still want more.

Orange juice has a drastically higher GI than oranges because your body more rapidly absorbs sugar from juice than from pulp. It's not just the quantity.

The process of juicing already leaves some waste out and you are probably also removing the pulp from the juice itself.

OP was talking about the differences between eating a certain food and eating that same thing after liquifying it as a whole.

>I wouldn't eat 3 oranges in a row

I would! I tend to go overboard on fruit if I don't stop myself. Apples, oranges, blueberries, cantaloupe, all so delicious...Not always pleasant for digestion and probably a bit of sugar rush, but do you know of any more serious health effects?

Eating too much sugar has serious long term health effects.

Ignoring the effect on your teeth, it was my understanding that the fibre in fruit helped counteract many of the negative effects of fructose (at least, keeping your insulin in check). I don't have any proof on hand, so perhaps I'm wrong.

There's afaik a rather big difference between freshly squeezed orange juice, and fruit juices that have been pasteurised. I'm not sure there's that big a difference between eating an orange and drinking the juice - other than the simple fact that the orange will contain "more stuff" that is "not sugar" than the juice - hence it'll be easier to increase sugar intake by drinking, say a litre of orange juice a day, and eating some food - rather than eating six(?) large oranges and being reasonably full.

Absolutely. I'm assuming eating an orange would have more fibre than a squeezed orange.

Buying "smooth" (no "bits") juice I would assume is missing most of the fibre.

Fructose is low GI, so there is a small insulin response only.

Ah, you are right. I think I'm misremembering. I'm basing most of what I wrote on https://www.youtube.com/watch?v=dBnniua6-oM but I watched it years ago and my memory isn't the greatest. (I also didn't fact check the video's content, so... grain of salt and all that, it does seem well sourced though)

The blending idea I've not seen any research to back up what you have said.

Surface area of absorbing fructose could logically affect your body (think Higher GI), as could enzymes in saliva. So while it's the same stuff you might well absorb it in worse ways for your body...

As far as the specific example of blended fruit, I seem to be on solid ground.[0][1] However, starches do change properties depending on form, which is probably similar to what you were getting at with fructose absorption.[2] I was mostly complaining about claims that micronutrients lose bioavailibility when not provided in their "natural" form.

[0] https://www.quora.com/Does-blending-reduce-the-nutritional-c...

[1] http://www.livestrong.com/article/548978-does-fruit-lose-its...

[2] https://www.ncbi.nlm.nih.gov/pubmed/3046297

Do you tend to swallow raspberries whole, or chew them first?

Are you saying chewing is as effective as blending? Are you saying saliva doesn't have enzymes in it that might affect things?

Point to research or I'll assume you are just making things up! Just to be clear I'm not saying I'm right I'm saying I doubt we have proved it...

I spit in the blender, of course.

Actually that was how some forms of alcohol used to be made, for example sake in Japan.

> The first sake, kuchikami no sake, (口噛みの酒) or "mouth-chewed sake," was made by people chewing rice, chestnuts, millet, and acorns and spitting the mixture into a tub, where the enzymes from saliva converted the starches to sugar. This sweet mixture was then combined with freshly cooked grain and allowed to naturally ferment.

It might seem like a disgusting practice to contemporary eyes, but it does show the power of human saliva and how one should not discount the process of chewing food. Drinking a liquid vs actively chewing, imbibing the chewed food with your saliva, definitely does not lead to the same thing.

From my experience, when people vomit after eating it comes up pretty recognizable.

Everything I do not understand in detail is just an "urban myth".

With nutrition you can safely assume most things you hear are bullshit.

I do not think so. The statement that keto is the best diet even if it causes rectal bleeding sounds reasonable to me [source: HN]. I go now and take a fat-shake. Cheers!

I was on keto. It worked. No rectal bleeding. I also didn't die of various stuff I was supposed to. I'm close to getting jailed though, because I fear that at some point I'll break and punch the next person who tells me that artificial sweeteners cause cancer.

They can cause neuronal damage through excitotoxicity [0][1]. I've never heard of keto before, but I would be wary of aspartame and MSG.

[0] https://www.ncbi.nlm.nih.gov/pubmed/7854587

[1] http://americannutritionassociation.org/newsletter/review-ex...

The American Nutrition Association is not a credible source. And they're using a discredited source - he's promoted several outright conspiracy theories. (I mean, fucking chemtrails even).

For the downvoters:

Anyone can join the American Nutrition Society as a professional member. Minimal checks are made of professional registration - you just need to paypal the fees.

Russel Blaylock's wikipedia article says:

https://en.wikipedia.org/wiki/Russell_Blaylock

> Blaylock has endorsed views inconsistent with the scientific consensus, including that food additives such as aspartame and monosodium glutamate (MSG) are excitotoxic in normal doses and that the H1N1 influenza (swine flu) vaccine carries more risk than swine flu itself.

> Advertisements selling the 'Blaylock Wellness Report' at newsmax.com contain claims of additional health dangers, including fluoridated drinking water, fluoridated toothpaste, vaccines, dental amalgam, cholesterol drugs, pesticides, and aluminum cookware.[23]

> In April 2013, Dr. Blaylock entered his endorsement of the chemtrails conspiracy theory on an internet radio program called Linderman Unleashed Radio Show where he cited increased levels of aluminum in water bodies and nature with his common sense observations of the skies. He proposed the conspiratorial and criminal aircraft spraying by governments of nano toxins for some supposed global, emergency purpose

This is a laundry list of woo topics, and it should be obvious that he's no longer a credible source for anything.

It was surprising to me to see that fluoride free toothpastes exist. They're sold regularly at Whole Foods. And you can check on the American Dental Association page which products earn the ADA Seal... none of which avoid inclusion of fluoride.

http://www.ada.org/en/science-research/ada-seal-of-acceptanc...

Fluoride collects in your pineal gland. There is no study (AFAIK) that says it harms the function of the pineal gland, but when I armchair-researched this a few years ago, it seemed no one is quite sure that it is benign.

The most significant benefit from brushing comes from the mechanical action, not from the toothpaste or any compound within. Personally, I use fluoridated toothpastes, but I can understand people who don't.

People like to point to scientific consensus as proof (by authority), but consensus changes with time: Trans fats are no longer good. Fats are no longer bad. Stomach ulcers are now caused by bacteria. Cholesterol intake no longer matters. Dinosaurs are no longer extinct (they are birds now), and had features. Patient zero did not bring HIV to the US.

It may or may not be benign. But I know that fluoride prevents cavities by reinforcing your enamel and that's why the ADA recommends it. So whatever the accumulation of fluoride does to my pineal gland, I'll trade that for the protection fluoride affords.

I know unfluoridated toothpastes are clinically proven to work in cleaning your teeth. But I need anti-cavity protection too.

(My mom's a dental hygienist. She'd kill me if she found a cavity.)

It would be so sad if you get jailed because of an "urban myth".

Someone could at least write a magazine article proving that artificial sweeteners cause incarceration.

Analogous to the fact that it is very hard to study the nutrition and long-term effects of Soylent on a big scale, with a diverse set of people, the same seems to be true for "normal" food. How do you even _define_ a "regular diet"? The exact diet varies from person to person, even from week to week!

Even though we've had "normal diets" for way longer, it is impossible to study those effectively without first closely defining the diet in question (which is effectively the same as feeding Soylent, minus the powderization and conservation).

Following that, it should be much easier to closely examine the effects of Soylent on people than it is to study any other non-standardized form of nutrition. And yet every "fact" about Soylent you read is purely anectodal.

I take it you didn't study food science. It's called oxidation, look it up. Also, some foods are made more bioavailable when soaking and blending, and sprouting, cashews.

Curious what are your thoughts on GMOs.

Wouldn't it be ironic if one of the GMO ingredients in Soylent was causing the kind of allergic reaction that organic activists are always warning about thus proving the hazardness of GMOs. This is sheer speculation but had to share the thought.

Not unlikely, most GMOs are modified to increase resistance of them for pesticides, or for them to produce pesticides themselves.

And these increased pesticides often also cause several reactions in humans.