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Comment by qeternity | Hacker News Reader

Metabolically, fruit is not very different from “sugar sweetened foods and beverages” (and imho gram for gram, fructose is worse than sucrose). The same goes for whole grains.

Fat is the most calorie dense nutrient. The human race has spent a majority of its time just trying to stay alive. Up until very recently, this meant eating substantial quantities of fat, and specifically animal fat.

Harvard Medical is part of the problem. People stop getting published if you’re contra-establishment, which means you stop getting juicy grants and donations.

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> Metabolically, fruit is not very different from “sugar sweetened foods and beverages” (and imho gram for gram, fructose is worse than sucrose). The same goes for whole grains.

Most fruits* and whole grains have higher fiber content, higher nutrient density, and lower glycemic indexes than sodas and junk foods that are high in added sugar. There is strong evidence that high added sugar (including added fructose) consumption contributes to health issues like obesity and type 2 diabetes, but no evidence that fruits and whole grains in general are unhealthy for most people.

* Excluding fruit juices

That's true to an extent, but everything in moderation. If you consume a large quantity of fruit in a short period of time then your body will turn the excess fructose into fat.

https://peterattiamd.com/rickjohnson/

https://www.scientificamerican.com/article/ancient-mutation-...

An extent? Was anything claimed not actually true?

If you consume an excess of calories no matter what the food you'll gain weight, so that seems like pointless pedantry.

Please go back and read my comment, and the linked pages, more carefully. Obviously a positive energy balance will result in weight gain. The issue is that excess fructose will specifically cause fat gain as opposed to gains in other types of tissue. Other nutrients don't activate the same metabolic pathway. This is a crucial distinction and not pedantry.

I read your comment and one of the linked pages was a summary (and I'm not listening to the 2 hour discussion) and the other behind a paywall. Are you claiming that a large excess of calories due to consumption of which other nutrients than fructose does not cause adipose tissue increase? Because that would be pretty astounding. Can you copy a verbatim quote from the scientific american article (or timestamp from the video) that supports this?

Also to add: the chances of most people binging on fresh fruit are pretty low.

(Processed fruit like raisins and fruit juices are another story.)

> Most fruits* and whole grains have higher fiber content

True

> higher nutrient density

False (this is the problem with processed foods - they are dense and people eat too much)

> and lower glycemic indexes

True, but ignores a whole host of other considerations such as metabolic pathways.

> There is strong evidence that high added sugar (including added fructose) consumption contributes to health issues like obesity and type 2 diabetes, but no evidence that fruits and whole grains in general are unhealthy for most people.

False. There is evidence that people eat far too much, full stop. And much of that excess comes from cheap refined carbs. This is a socioeconomic observation and not a metabolic one. You are confusing correlation and causation. It’s comments like these that are the reason we have such horrible nutritional advice.

My comment was about how sources of carbohydrates (and all food for that matter) are more similar than dissimilar: drinking a soda and taking a multivitamin is metabolically not much different from eating fruit. That doesn’t mean people should drink soda instead of fruit, but it does mean people should consume less of both. You are better off having some vegetables, nuts or animal fats/proteins. Fruit isn’t healthy just because it’s natural.

Nutrient density is not a measure of calories per mass or volume (energy density). This is what nutrient density means in the context of nutritional science:[1]

> The nutrient density standard, as defined by the FDA, is the ratio of the amount of beneficial nutrients relative to the food’s energy content per reference amount customarily consumed. The more nutrient-dense foods are those that contribute more beneficial nutrients than calories to the overall diet.

Fruits and vegetables generally have higher nutrient density than most other food categories:[2]

> As expected, we found that fruits and vegetables were nutrient-dense in relation to their energy content.

> However, the data unambiguously showed that fruits and vegetables were nutrient-rich in relation to the little energy that they provide. Although fruits and vegetables suffer when assessed on the calories/price ratio, they represent extremely good value when assessed using the nutrient density score and the nutrient to price ratio.

Sugar-sweetened beverages (SSBs), the most common source of added sugars, contributes to obesity and type 2 diabetes (T2D):[3]

> Consumption of SSBs has increased markedly across the globe in recent decades, tracking closely with the growing burdens of obesity. These beverages are currently the largest source of added sugar intake and the top source of daily energy in the US diet. The cumulative evidence from observational studies and experimental trials is sufficient to conclude that regular consumption of SSBs causes excess weight gain and these beverages are unique dietary contributors to obesity and T2D. Compelling evidence indicates that reducing SSBs will have significant impact on the prevalence of obesity and its related diseases, especially T2D.

Consuming at least 2 servings of fruit and 3 servings of vegetables per day (excepting fruit juices, starchy vegetables, and potatoes) is associated with lower mortality:[4]

> In the 2 prospective cohorts with many repeated measurements of diet and up to 30 years of follow-up, we observed that a higher intake of fruit and vegetables was associated with a lower risk of total mortality and cause-specific mortality in a nonlinear manner. Our analysis in the NHS and the HPFS and in a meta-analysis of 26 prospective cohort studies documented that intake of ≈5 servings of fruits and vegetables daily was associated with the lowest mortality, and higher intake was not associated with additional risk reductions in mortality. The thresholds of risk reduction in mortality were 2 servings daily for fruit intake and 3 servings daily for vegetable intake. Higher intakes of most subgroups of fruit and vegetables were inversely associated with mortality, whereas intakes of starchy vegetables, fruit juices, and potatoes were not associated with mortality.

And again, there is no evidence that fruits and whole grains in general are unhealthy in a balanced diet for most people.

Eating fruits is not equivalent to combining sodas with multivitamins. Fruits have fiber, antioxidants,[5] and other compounds that are absent from multivitamins.

[1] https://academic.oup.com/ajcn/article/82/4/721/4607427

[2] https://www.researchgate.net/publication/7446672_A_Nutrient_...

[3] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5325726/

[4] https://www.ahajournals.org/doi/10.1161/CIRCULATIONAHA.120.0...

[5] https://en.wikipedia.org/wiki/List_of_antioxidants_in_food

You really, really do not understand correlation vs causation. And you're so convinced you're right, you're hawking terrible science. Every claim you make is hedged: "...in a balanced diet". Yeah of course, in a balanced diet, nothing is unhealthy because by definition the unhealthy bits are balanced out somewhere else. What are you actually trying to prove here? Your grasp on these topics is tenuous at best. Antioxidants? Do you only get your nutritional advice from Whole Foods? Do you know how weak the science around dietary antioxidants is and our understsanding of free radicals in general? Fine, don't like my soda analogy...mix some psyllium husk in with your soda. Now you have fiber...this doesn't change the metabolic pathway in any material way. You don't understand what I'm talking about.

Honestly, these kinds of views are why the American diet is so poor. You so desperately want to prove a narrative, irrespective of what the science actually says. You're focused on nutrient density, as opposed to the real issue: calorie density. We don't need to run around inventing new standards for "nutrient density"...we need to get people to eat less. And most people are over eating due to chronically elevated insulin levels and reduced insulin sensitivity on the back of carbohydrate based diets. People aren't dying prematurely from specific vitamin, mineral, or EFA/EAA deficiency. They are dying because they are obese. Even a horrible diet is going to provide most nutrients in sufficient quantities. Outside of a select few nutrients, the human body can synthesize and up/down regulate processes to accommodate varying levels of "nutrients"...this is not what people in the developed world grapple with. But sure, let's all eat wheat cereal with oat milk and fruit and honey for every meal. So healthy.

I used the words "balanced diet" to rule out, for example, someone eating only fruits and nothing else. I hedge my words carefully because I don't want to make overly broad claims that are not backed by evidence, as you are doing. I do understand what you are talking about, and I have been pointing out that some of your claims are contradicted by or not supported by evidence.

You're accusing me of all kinds of things without providing a single piece of evidence to back up your claims. You're also putting words in my mouth that I never said, and claiming I take positions that I don't support. For example, I never recommended oat milk (which is not a whole grain product), honey (which is classified by the FDA as added sugar when not sold as a single ingredient), or breakfast cereals (which are often sold sweetened with added sugar and usually not whole grain). That is a straw man.

I agree that people who are consuming too many calories in their diet should reduce the amount of calories that they consume. However, that has nothing to do with the fact that fruits can be part of a healthy diet, which is backed by evidence from a wide body of research and not contradicted by any evidence that fruits are unhealthy for most people. If fruits are unhealthy for most people as you claim, you should have no problem finding peer-reviewed research of similar or higher quality that backs up your assertion.

Here's yet another review that confirms that fruit consumption has stronger anti-obesity than pro-obesity effects in most cases, which also explains why supplements and soda are not equivalent to fruits:

> Previous studies of the effects of fruit on obesity have shown that their anti-obesity effects are greater than their pro-obesity effects in most cases, as demonstrated in this review. Moreover, the final outcomes of these anti-obesity studies support the inclusion of higher amounts of fruit in our daily food intake to reduce weight, as well as promote a healthy life style by increasing physical activity and reducing the intake of sugar and fat. However, most types of fruit contain large amounts of simple sugars, which are well-known contributory factors to obesity and obesity-related diseases. Therefore, the high level intake of particular forms of fruit such as fruit juice is not advisable in certain age groups, especially children. In addition, it has been suggested that plant fiber and phytochemicals may be responsible for the anti-obesity effects of fruit, but cereals are also rich in phytochemicals and fiber yet they have no remarkable anti-obesity effects. Therefore, more human trials are required to address these two mechanisms. In addition to the possible anti-obesity mechanisms discussed above, we consider that various other important unknown components present in fruit may be responsible for preventing obesity. Furthermore, the anti-obesity properties of known fruit components need to be verified. Thus, future research should be focusing on identifying anti-obesity components in fruit as an urgent and important task in order to understand the scientific mechanism of obesity but also to develop a method for controlling obesity by increasing fruit consumption.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5084020/

From what I've read though, the sugar content in fruit isn't metabolised in the same way as say a bar of chocolate.

This is why I said it was worse. I’m being downvoted by people who don’t actually know the science.

Fructose must be metabolized by the liver, whereas glucose can be metabolized directly in skeletal muscles as glycogen.

People are disagreeing with you because you claimed, without evidence, that eating fruits and whole grains is similar to consuming sugar-sweetened foods and beverages.

Fructose in fruit is trapped in the fibrous flesh and takes longer to digest. As it progresses through your system, a good portion is consumed by the gut microbiota so it doesn't have the same impact on your body.

Processed food using high fructose corn syrup, is not going to be digested in the same way as an apple.

A good portion? How much? What impact on the body are you referring to? How is the digestion different?

I would love to engage, but I have nothing to engage with. Yes, fiber impacts digestion, which has nothing to do with metabolic pathways. But even such, high sugar fruits have similar GIs to HFCS...the digestive impact of fiber is relatively small (compared to fats and amino acids, especially non glucogenic).

The team, from the University of Hohenheim, Germany, analysed the microbiota composition of 12 healthy females following consecutively different high-fructose diets, first a fruit diet (100 g/day fructose from fruit and vegetables) and then, after a low-fructose phase, a high fructose syrup (HFS) diet (100 g/day fructose from syrup) and characterised the responses of bacterial communities after the different dietary interventions.

The report concludes that a high-intake of fructose syrup causes a reduction of beneficial butyrate producing bacteria and a gut microbiota profile that may affect unfavourably host lipid metabolism, whereas high consumption of fructose from fruit seems to modulate the composition of the gut microbiota in a beneficial way supporting digestive health and counteracting harmful effects of excessive fructose.

Besides a high fructose content, the authors note that the high fruit diet was characterised by a relatively high content of fiber. They therefore point out that observed alterations in gut microbiota may at least partially reflect changes driven by a higher intake of fiber rather than changes in response to the high-fructose consumption.

Fibre is an important component of the human diet and has known health benefits including lowering cholesterol and improving blood glucose responses. Dietary fibre as a prebiotic has specific effects on the microbial populations and its function as individual taxa have been shown to selectively metabolise discrete fibre structures.

To me, although I don't really know a lot, it seems quite logical that fruit is generally good for you and quite hard to overeat. We've been consuming fruits for thousands of years and although agriculture may have increased availability and nutritional value, comparing 10g of fructose found in an apple to 10g of fructose found in candy is nonsensical.

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