Lo carb or low fructose?

(Tim Cee) #1

(Take time to smell the bacon) #2

Low carb or low fructose? Yes.

Seriously, though, while Dr. Lustig is not, himself, a low-carber, his campaign to get people to “Just Eat Real Food” has much the same effect. By cutting out sugars, refined grains, starches, and the unhealthy fats found in industrially-processed foods, people almost automatically go low-carb and become healthier.

(Tim Cee) #3

Are they equally effective at treating metabolic syndrome? Are they seperable?

(Take time to smell the bacon) #4

Cutting back way back on, or eliminating, sugar and ethyl alcohol has been shown to fairly quickly reverse fatty liver disease, which is one source of insulin resistance, and therefore metabolic syndrome. Another source of insulin resistance is reduced greatly by cutting back significantly on carbohydrate intake, which significantly reduces hyperinsulinaemia. Hence, do both.

(Tim Cee) #5

That’s been my opinion for a long time. However, the presentation linked above seems to claim that people eating a low fructose diet have the same average outcome as people on a low carb diet, suggesting it’s the fructose included in most sugary ingredients. So a high fiber grain would be fine for a person who’s not sensitive to lectins?

(Take time to smell the bacon) #6

As I mentioned, Dr. Lustig is not a low-carber, himself. But his take on the science of fructose as a long-term toxin appears to be sound, and well-accepted in the literature. His claim that the effect of fructose on the human body meets the same criteria Bradford-Hill used to condemn tobacco smoke also appears to be valid. I think he and Dr. Phinney would have an extremely interesting conversation, if we could lock them in a room and write down all the studies they cite.

In addition to the other causes of insulin-resistance I mentioned in my earlier post, BTW, some people have begun blaming the damage caused by the polyunsaturated fats in vegetable oils as a major culprit, as well.

(Tim Cee) #7

I’m inclined to think it’s an “all the above,” on manufactured food products. God and nature haven’t conspired to make us sick and miserable according to any world view I would take seriously. It only makes sense that engineered food substitutes are a good place to look for reasons why our health has recently been in decline. Regardless of the macros, I’m inclined to cook food ingredients as found in nature and not eat year-round what can’t be found year-round.


I say low carb, the fear of fructose is near BS. HFCS… sure, natural fructose from fruit? C’mon.

(Take time to smell the bacon) #9

It’s the amount of fructose that hits the liver at any one time that is the problem. The metabolic pathway in question can handle only a certain amount of fructose, ethanol, or branched-chain amino acids (alone or in combination) at a time. Above that limited rate, de novo lipogenesis begins, leading (after prolonged excessive exposure) to fatty liver disease, steatohepatitis, cirrhosis, and, eventually, death.

Fructose accompanied by the fibre from an entire fruit is one thing, but in the form of juice or soda, which completely lack fibre, it is easy to overwhelm the above-mentioned pathway with the quantity of fructose ingested. Because of the fibre they contain, no one can eat enough apples in one sitting to get the amount of fructose found in a single glass of apple juice, Dr. Lustig says. He also states that the fibre in whole apples slows down the absorption of the fructose they contain, to a rate that the liver can handle without damaging itself.

What originally clued researchers in to the problem was the diagnosis of fatty liver disease in populations, such as children, who are clearly not alcoholics. It’s not for nothing that Dr. Lustig’s paediatric obesity clinic at UCSF forbids its patients to drink anything but milk or water. One study they did on some of their patients showed that merely eliminating fructose from their diet, while retaining the caloric intake and not worrying about the carbohydrate intake, was sufficient to clear up their fatty livers in as little as ten days, if I recall correctly.


Fruit juice even when 100% fruit juice. Without the fiber to help slow digestion of the fructose, the liver becomes overwhelmed quickly. So, giving kids juice instead of pop seems innocuous to most. However, the load on the liver is unmanageable.

Is HFCS a problem? Surely. Is titration of fruit juice a better alternative? No. Is eating an orange or two a day harmful? I don’t think so.

(Tim Cee) #11

Now, I was only listening and I couldn’t see the visual aids, but it seemed to me like he was saying that fructose can only be metabolized in the liver and is converted into fat in any amount. So the upper limit of fructose has to be no more than what produces an innocuous amount of liver fat—have he amount which is being burnt off before it has to accumulate. It seems like he was implying we shouldn’t give our kids any more fruit than we would beer. He did mention fiber, however. The amount of fiber he claims would be appropriate to balance a normal daily sugar intake would be in the neighborhood of 300g. Personally I don’t think I can eat that much fiber without having a bowel malfunction. I need to re-watch because I’m getting the idea I misunderstood some stuff.

(Tim Cee) #12

Did you watch the video? It’s pretty solid on the science.

(Tim Cee) #13

What is HFCS? Oh duh: high fructose corn syrup.

Hey fructose corn syrup has roughly the same proportion of fructose as cane sugar. There’s no effective difference. Just because an organic chemical comes from a natural source doesn’t transform it from a toxin to a safe substance. Anyone for a draught of crude oil?

(Tim Cee) #14

I think the milk/water only rule is something I may take home. And it’s gonna be whole milk.


Yeah, sucrose is 50/50 glucose/fructose. I was responding to the other post about HFCS. I believe HFCS is something like 45/55 glucose/fructose, not materially different than sucrose, I agree.

However, the key takeaway is inundating the liver with a fructose load higher than it can handle, which will cause conversion of excess fructose to be made into fat. Fruit isn’t the biggest issue because the fructose load is attenuated by the fiber. However, when one consumes fruit juice the fiber is not there to help slow digestion of the fructose and it overwhelms the liver.

Incessant overloading of the liver with fructose presents as fatty liver. This will cause fatty pancreas and eventually hyperinsulinemia results. So, hyperinsulinemia can be the effect of the aforementioned path or of glucose overloading the pancreas causing fatty pancreas and then fatty liver.

Some studies have shown 30g of fructose as the limit our livers can handle at once. When we tell our kids they should drink apple juice or orange juice as a healthy alternative to some other sugary beverage, it’s causing meaningful harm. Not just kids, but they seem to be the targeted market.

So, to answer the question: low carb or low fructose? Yes. I believe overloading the liver with fructose can cause harm more quickly to most of us versus high glucose. So, avoid fruit juices, and eat whole fruit if consuming fructose. For those of us who are more intolerant to glucose, low carb is the way to go. This implies low fructose. I do think there is a place for some whole fruits on keto though if that tickles one’s fancy. Half an orange, some berries, etc. could be helpful for some to get micronutrients they might be lacking with a low carb load option that is fructose and not glucose.

(Tim Cee) #16

Is that 30g/day or /meal. I just rewatched the video and it seems pretty clear Lustig says all fructose that is absorbed in digestion goes to the liver and is used to make fatty liver. It seems the only way fiber would matter is to fill the stomach and limit the available volume. Personally, I find fruit to be mostly sugar water. If you squeeze a fruit dry, the amount of fiber your left with is pretty small. I’ve never succeeded in filling on fruit. I’m putting fruit in the same category as desert.


That’s a fair summary. The subjects were obese children and their fructose intake was swapped out for other carbohydrate sources, e.g. brown bagels. In Lustig’s own words, the food given was still ‘junk’.

(Take time to smell the bacon) #18

That’s right. So the daily sugar intake needs to be reduced to, at most, a level that allows the amount of fibre we can manage to balance it.

Or, we could simply eat no sugar at all. For sugar addicts, this is actually the easiest, simplest way to go on.

(Take time to smell the bacon) #19


(Take time to smell the bacon) #20

First, it’s 30 g/day. Second, the effect of the fibre in whole fruit (as opposed to juice, where the fibre has been destroyed) is to slow the absorption of the glucose and, hence, the fructose in the fruit to a rate that the liver can handle. Sorry—thought I’d put this in one of my earlier posts. Guess not.