Effect of Low-Fat vs. Low-Carb Diet on 12-Month Weight Loss in Overweight Adults | Hacker News Reader

Effect of Low-Fat vs. Low-Carb Diet on 12-Month Weight Loss in Overweight Adults

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56 pointsnradov64 comments

Fulltext: https://www.dropbox.com/s/cbpt3bw8ql310kr/2018-gardner.pdf?d...

Worth noting that the genetics here was just 3 SNPs based on a 2010 candidate-gene study of apparently n=133 (it was never published, it's just a conference talk, based on the citation & description of the work in https://www.wsj.com/articles/SB10001424052748703862704575099... ), which made the absolutely crazy claim that "those with a genetic predisposition to benefit from a low-carbohydrate diet lost 2 1/2 times as much weight as those on the same diet without the predisposition". So unfortunately, their total failure is exactly what you would predict from a non-GWAS-derived set of SNPs and the result is meaningless. This tells you nothing about whether SNPs can predict or cause more/less weight loss, be used to optimize diet choice, or have any cross-racial differences, despite people apparently interpreting it that way.

The key thing for these diets is the ratios of Carb/Fat/Protien :

In the HLF vs HLC diets, respectively, the mean 12-month macronutrient distributions were 48% vs 30% for carbohydrates, 29% vs 45% for fat, and 21% vs 23% for protein.

Both of those diets seem fairly balanced. A typical ketogenic diet (high-fat, low-carb) is usually < 10% calories from carbohydrates, 20-30% from protein (depending on exercise) and 60-75% fat calories. It seems unlikely any of the HLC participants would have gotten into ketosis, so I don't see this study as being relevant to the current debate over the efficacy of ketogenic diets.

Low-Carb proponents don't necessarily disagree that 'a calorie is a calorie' in the physics sense. We just feel there's no need to be hungry when you can eat to satiation and still lose weight, and that unnecessarily high glucose in the bloodstream is not good for you anyway.

Complex carbs like potatoes are some of the most satiating and nutritious foods you can eat:

https://scottabelfitness.com/potato-and-the-satiety-index/

High fat diets can also be satiating but there are a lot of downsides to eating saturated fats, which make up most of the fats in the typical keto/paleo high fat diet.

https://nutritionfacts.org/video/the-saturated-fat-studies-s...

I guess it depends on how a potato is prepared. The guy in the link eats baked potatoes which I suppose would be pretty filling. Personally I've found most 'filling' foods I eat when (trying to get back to) low-carbing are: cauliflower, eggs, paneer (a type of Desi cheese), coconut, and beans/legumes.

Boiling potatoes provides the best glycemic profile. Letting them cool before you eat them increases the amount of resistant starch further:

https://yurielkaim.com/resistant-starch/

Legumes are a very healthy food on a lot of counts.

Missing from the title is the qualifier "healthy", as in "healthy low-fat" diet vs "healthy low-carb" diet. What does "healthy" mean, here? It's not defined in the abstract.

The closest I got to definition of "healthy low X" was a general description of the approach in the paper:

"Briefly, the main goals were to achieve maximal differentiation in intake of fats and carbohydrates between the 2 diet groups while otherwise maintaining equal treatment intensity and an emphasis on high-quality foods and beverages.

Thus, participants were instructed to reduce intake of total fat or digestible carbohydrates to 20 g/d during the first 8 weeks. Higher priorities for reduction were given to specific foods and food groups that derived their energy content pri- marily from fats or carbohydrates. For example, the reduction of edible oils, fatty meats, whole-fat dairy, and nuts was prioritized for the healthy low-fat group, whereas the reduction of cereals, grains, rice, starchy vegetables, and legumes was prioritized for the healthy low-carbohydrate group.

Then individuals slowly added fats or carbohydrates back to their diets in increments of 5 to 15 g/d per week until they reached the lowest level of intake they believed could be maintained indefinitely. No explicit instructions for energy (kilocalories) restriction were given. Both diet groups were instructed to (1) maximize vegetable intake; (2) minimize intake of added sugars, refined flours, and trans fats; and (3) focus on whole foods that were minimally processed, nutrient dense, and prepared at home whenever possible."

I find the last sentence interesting, reminds me of Michael Pollan's quip: "Eat food. Not too much. Mostly plants."

Conclusions: In this 12-month weight loss diet study, there was no significant difference in weight change between a healthy low-fat diet vs a healthy low-carbohydrate diet, and neither genotype pattern nor baseline insulin secretion was associated with the dietary effects on weight loss. In the context of these 2 common weight loss diet approaches, neither of the 2 hypothesized predisposing factors was helpful in identifying which diet was better for whom.

I wonder which of the two is easier to keep. Feeling hungry most of the time is little joy and leads to relapses.

Oh but. . . "weak willpower", and "immorality", and "fat people deserve their misery and shame". . . we really need to maintain our comfortable mindset.

I'm not sharing this because it doesn't confirm my self-tested and proven beliefs. #NoCarbsForLife

29% cal from fat isn't really low fat. It would be interesting to see a study on lower fat diets.

Also, 30% of calories from carbs (on the so-called low-carb diet) is not really low-carb. As mentioned in another comment, for a 2,000 calorie diet, that's 600 calories from carbs! Most low-carb diets aim way lower than that because they aim at reaching a state of ketosis, where your body is essentially burning fat instead of sugar for energy. This might be something like 20-50 grams per day, depending on a lot of factors like specific carbs consumed, etc. This is the stage where a lot of the health benefits including increased energy, no afternoon crash, weight loss, etc. come in.

I realized recently that I was getting fat (4 inches of waist size increase in just a couple years), so for the past couple months, I've tried restricting my calories. At first, I tried cutting out things that are just ridiculous like beer and bread. In the past week or so, I've gotten more 'restrictive' and have been trying to eat almost exclusively meat. I'm not counting calories or anything like that, I just eat until I'm full and then I stop. I have lost 20 lbs in the past two months, and I feel much better overall. I have way more energy than I did before and I fart a lot less.

I can understand if it sounds extreme, but look at the standard American diet. Since the food pyramid was introduced, with a base of grains, people have gotten nothing but fatter, more diabetic, more heart attacks and stokes, etc. While there are essential fats and proteins, there are NO essential carbohydrates. I'm not sure if I'm going to stay on this diet forever, but it doesn't seem like the mainstream diet is very healthy, so I'm going to listen to what my body tells me and use reason to try to get out of this mess.

I've done both keto and whole-foods-plant-based diets.

Both lose weight - but I feel a lot more energy on a starch based diet. Whole plant foods contain the right amount of fat (10%). Who cares about farts when I never get constipated. With a little exercise and a starch based diet I was able to lose 80lbs. When I started introducing fats and added refined sugars - the weight came back. The fat you eat is the fat you wear.

Long term ketosis is not optimal health.

https://www.ncbi.nlm.nih.gov/pubmed/22850317

https://www.ncbi.nlm.nih.gov/pubmed/11108325

Look at cheese consumption and it tracks national weight gain. We're taking in way more fat today than long ago.

http://www.pcrm.org/images/media/blog/cheese_consumption.jpg

But we're taking more calories overall - so people get to blame whatever they want.

Starches powered all civilizations up to the 20th century. Only when we started consuming lots of meat and purified sugars and white flour did we really gain weight.

I'm guessing they used a random sample to study the diets hopefully and also this would generally mean I believe that any general diet low in fat or carbs can lose weight because they listed that participants still lost 5 to 6 kg no matter the diet?

Ketosis can apparently lead to more weight loss because ketones are less efficient vehicles of energy in general. Additionally, unused ketones can be eliminated through sweat, urine, and breath.

Apparent to what evidence?

The Krebs Cycle I am guessing.

>>In the HLF vs HLC diets, respectively, the mean 12-month macronutrient distributions were 48% vs 30% for carbohydrates, 29% vs 45% for fat, and 21% vs 23% for protein.

30% carbs is hardly "low-carb".

Indeed, most low-carb diets suggest 50g or less carbs per day - 200 calories or less.

https://www.dietdoctor.com/how-low-carb-is-low-carb

edit: why am I being downvoted?

That's exactly what I was thinking. Also, to do this across 12 months definitely means that 90% have dropped out after 30 days and shouldn't be counted. Those that treat it as a short term diet are bound to rebound. In the end you need to see this as your permanent way of eating.

I've found even 50g still too high.

30% of a 2000-calorie diet is going to be 150g of carbohydrates per day. Not very low carb at all.

> 30% of a 2000-calorie diet is going to be 150g of carbohydrates per day.

600g

There are 4 calories per gram of carbohydrate.

50g is still high. Most people in low-carb communities talk about "low carb" as being under 20 grams per day.

Ketogenic is under 20g per day; low-carb is usually <100g.

Unsurprising results- calories intake & expenditure defines weight loss/gain, not other nutrition information like fat, carbs, vitamins, etc.

I'm actually relieved by the result. It makes things make sense again a little more.

It is surprising if you believe the insulin-obesity hypothesis. A lot of people do these days.

I my mind the point of these special diets is to alter the food habits making it so that you take in less total energy. By essentially forcing you to think more about your food.

Not that one diet wound automatically burn more energy than the other.

True; however, they may be very different practically. Few people are going to measure calories for every single thing they eat. Most will rely on the sense of hunger and urge to eat certain things. I wouldn't be surprised if low-carb diets outperform low-fat ones in that department, since carbs tend to keep people urging for more through rapid blood sugar fluctuation.

> I wouldn't be surprised if low-carb diets outperform low-fat ones in that department, since carbs tend to keep people urging for more through rapid blood sugar fluctuation.

This is exactly why low carb has works so well for me. My cravings for snacks become virtually disappear.

That result is literally what this study is saying they didn’t find.

Perhaps you can make the argument that the study is flawed statistically or that 12 month weight loss is not long term enough or that the diet sessions caused the lack of difference?

This has been my experience, and I wonder if part of the efficacy of macronutrient-centric dieting is about cultivating self-control. That would be an activity that would be hard to measure in a study where the participants know they’re participating and have a sense of duty to remain committed. Healthy low fat vs healthy low carb will yield the same results, roughly, with the same caloric intake. Any macro combination will, really. But carbohydrate restriction is something I’ve personally found to be a good way to stay on the rails.

calorie intake and expenditure is a description not a prescription. this is about as useful as saying "make more money than you spend" in order to become wealthy. sure, that's true, but it won't help you make $10 million. how do you eliminate the desire to waste time and money on useless pursuits? that is the analogy we need to use to reframe this discussion. yes, there is a certain level of maturity and self-control involved, but you need to know what NOT to do first.

what is causing people the intense desire to overeat, and the intense lethargy that follows? probably insulin-spiking processed carbs and sugar. have you seen anyone in the throes of a carb addiction/crash cycle? it's damn near supernatural the amount of power these foods have over people.

at this point i consider them about the same level as cigarettes or alcohol. cheap, widely availabe, intensely addictive, and people who don't have a problem just telling you to "use less", "it's so easy". okay. sure.

"how do i graduate college?" "take more credits than it requires to graduate."

try telling this to the person who got sucked into the for-profit university and is $50k in debt.

the world is not as cut and dry as it seems, especially if you are burdened with a low IQ like the people who most easily fall for these schemes.

I'd say it's harder to quit eating badly than it is to quit cigarettes: You can live a long life without ever touching a cigarette again. But you won't get far with going cold turkey on food.

Food is also harder because a) the healthy option is more expensive and b) sugar and heavy processing is in so much of the food available that it's hard to avoid, or sometimes even detect.

Healthy food is often more expensive but there are healthy options for cheap. Rice, beans, and vegetables are all pretty cheap and can form the base for a lot of different meals. The hardest part for me eating healthy was having to relearn a completely different set of recipes

Good points, but there is something else going on.

If you travel alot you start to see that every culture is heavy on carbs: Rice, pasta, potatoes, noodles, bread. They are ubiquitous.

Find a frenchmen that isn't eating bread from first meal to last...or an asian with rice / noodles. Or an Italian with pasta / bread, etc.

There is something else wrong here. I don't pretend to know what it is, but it seems like its almost a "food culture" problem. The most immediate things you notice are: (a) Americans portion size is double the rest of the world, and (b) Americans eat very very fast.

Exactly. The idea that carbohydrates, which have been the staple of most human diets for millennia, are somehow suddenly toxic makes no sense. Complex carbohydrates are fine. What's gone wrong in the US is that we are eating more processed carbohydrates along with way more chicken and cheese and our portion sizes and overall calorie intake have gone up significantly:

http://geeksta.net/visualizations/calories-us/

Excess consumption leads to obesity, which correlates strongly with just about every major chronic illness. Portion sizes are a big part of the problem. Every time I come back to the US after living in Asia I'm shocked at how ridiculously large restaurant serving sizes are.

Meat and animal protein is actually more insulinogenic than many common carbohydrates.

https://www.drcarney.com/blog/entry/low-carb-theory-regardin...

Pretty much everybody agrees that eating a lot of sugar or processed simple carbs is a bad idea but the demonization of high fiber, complex carbs has no basis in science.

The idea that protein should be consumed instead of carbs couldbe due to them being equally insulinogenic to most 'complex' carbs, while also being the building blocks of muscle (rather than being stored on the body as glycogen). While I don't doubt that porridge, all-bran, and muesli enact a lesser insulin response, I'd rather eat the steak, which still beat out nearly all other carbs.

As a side-note, it would be interesting to see how the insulin responses would look if the test subjects were already following a low-carb protocol.

Eating too much protein is not healthy. And most Americans eat way more than the recommended amount:

https://www.healthline.com/health/too-much-protein#risks

You're also getting saturated fat and cholesterol with the steak, which is unhealthy despite recent efforts of some to cloud the issue.

If you want me to take the claim that "a high protein diet is unhealthy" seriously, then you're going to have to provide something better than that article.

"Weight Gain" due to increased protein consumption is disputed[1]. In fact the premise itself can be disputed just by noting that weight gain can present itself in the form of muscle gain.

Bad breath: ...really?

Constipation: "This is because high-protein diets that restrict carbohydrates are typically low in fiber." I'm sorry, but why do high protein diets need to be low in fiber? That doesn't make any sense at all - any diet can be low in fiber if you don't eat fiber.

Diarrhea: Author provides no source.

Dehydration and Kidney damage: Both prevented by drinking enough water.

Increased cancer risk: The issue with these studies is that they don't provide necessary controls. Most people who eat red meat regularly are not doing HIIT, strength training, or going for walks. They are not eating their red meat on a bed of spinach. They are eating it between two buns and with a side of steamy fries (which are known to cause cancer[2]). If we look at the actual mechanisms for carcinogenicity, we find that eating veggies, not burning your food, and not eating cured meats, are probably as likely to keep you cancer free than switching your steak to a super whole-grain diet. Don't forget to also have a healthy gut, which prevents colon cancer[3]

Saturated Fat / Heart Disease / cholesterol: Again, no long term studies have had the right controls in place to conclude that Saturated fat, in the absence of unhealthy carbs/meats, are actually harmful. Only 20% of the cholesterol in our bodies actually comes from our food. Saturated vs nonsaturated is a debate being waged between actual RDs. It's not just "an effort to cloud an issue".

Calcium Loss: Actually, more Americans experience calcium loss as a result of NOT getting enough protein. "Despite a widely held belief that high-protein diets (especially diets high in animal protein) result in bone resorption and increased urinary calcium, higher protein diets are actually associated with greater bone mass and fewer fractures when calcium intake is adequate. Perhaps more concern should be focused on increasing the intake of alkalinizing fruits and vegetables rather than reducing protein sources." [4]

Whether high fat and protein vs high carb low fat is "better", is going to remain debated until the end of time, because studies repeatedly show discrepancies. The fact is humans from different geographies have evolved over time to accommodate different diets. This is why we see things like lactose intolerance concentrated in some regions but devoid in others [5]. Imagine ALL of the other mechanisms for body health and how they have evolved over time in different regions, and consider how silly it is to attempt to expose those which are harmful using broad studies with poor controls over only certain populations - while ignoring the underlying mechanisms for the actual harm.

[1]https://jissn.biomedcentral.com/articles/10.1186/s12970-016-...

[2]https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4780226/

[3]https://www.ncbi.nlm.nih.gov/pubmed/26286349

[4]https://academic.oup.com/ajcn/article/87/5/1567S/4650438

[5]https://www.foodbeast.com/news/map-of-milk-consumption-lacto...

The dangers of excessive protein intake are very well documented. A simple Google search turns up so many references. Here's one from the Mayo clinic:

https://www.mayoclinic.org/healthy-lifestyle/nutrition-and-h...

Saturated fat intake has been shown to boost serum cholesterol and increase risk of CVD in literally hundreds of direct feeding mechanistic trials. Genetic variability of cholesterol is high enough that cross-sectional studies are not appropriate for studying this.

https://nutritionfacts.org/2016/10/04/how-to-design-saturate...

In other words, ingesting saturated fat and cholesterol will raise your cholesterol levels and increase your risk of CVD but your baseline risk depends a lot on your genes.

The mayo clinic link is actually reaffirming my opinion:

>For most healthy people, a high-protein diet generally isn't harmful, particularly when followed for a short time. Such diets may help with weight loss by making you feel fuller. However, the risks of using a high-protein diet with carbohydrate restriction for the long term are still being studied.

They are still being studied - poorly at that.

The second link is hilarious in that it fails to even describe the two types of LDL cholesterol, but lumps them both in as "bad" - which is typical of the "cholesterol is bad" crowd. In fact - the first study I clicked on in the nutritionfacts.org fails to mention the same. How can you do a study on cholesterol without even testing the two types of LDL? Frankly, it's embarrassing and is absolutely not mechanistic as you say.

Once again, these meta studies are attempting to show that a diet with lowered saturated fat intake is better in the long run than your average diet. This is not something that anyone is debating. However, it absolutely can not be misinterpreted as proof that high protein/saturated fat intake, in all cases, is bad. Which is exactly the mistake all of these authors are making, and is why there are many intelligent people on the other side of this discussion as well.

"Large" LDL is marginally less dangerous than "small" LDL but it still significantly raises your risk of CVD:

https://nutritionfacts.org/video/does-cholesterol-size-matte...

>"Large" LDL is marginally less dangerous than "small" LDL

Neither large nor small cholesterol are "dangerous" - it's black-and-white opinions like this that make the nutrition industry so difficult for laymen to follow. They are both healthy, in that without cholesterol you would die. Excessive amounts of certain cholesterols in ratio to others just happen to be symptoms of underlying eating disorders. The author states that:

"She ... argues that HDL, so-called good cholesterol, also rises maintaining the ratio of bad to good. This is the study she cites to support that assertion. But instead of cherry-picking this one study that she performed with Egg Board money, involving 42 people, if you look at a meta-analysis, if you look at the balance of evidence, the rise in bad with increasing cholesterol intakes is much more than the rise in good."

However, it is known that the ratio of HDL to total cholesterol is a just as good as if not a better predictor of heart health. That's why it is generally used... [1]

There are many documented cases of high protein diets (or more specifically - low carb) achieving better cholesterol ratios [2][3][4]. There are also many more studies that address the significance of LDL size, than what the author you linked addresses [4][5][6]

[1] Mensink, Ronald p., et al. “Effects of dietary fatty acids and carbohydrates on the ratio of serum total to HDL cholesterol and on serum lipids and apolipoproteins: a meta-analysis of 60 controlled trials” The American Journal of Clinical Nutrition 77.5 (2003): 1146-1155.

[2] Bueno, Nassib Bezerra, et al. “Very-low-carbohydrate ketogenic diet v. low-fat diet for long-term weight loss: a meta-analysis of randomised controlled trials.” British Journal of Nutrition 110.07 (2013): 1178-1187.

[3] Brinkworth, Grant D., et al. “Long-term effects of a very-low-carbohydrate weight loss diet compared with an isocaloric low-fat diet after 12 mo.” The American journal of clinical nutrition 90.1 (2009): 23-32.

[4] Merchant, Anwar T., et al. “Carbohydrate intake and HDL in a multiethnic population.” The American journal of clinical nutrition 85.1 (2007): 225-230.

[4] Otvos, James D., et al. “Clinical implications of discordance between low-density lipoprotein cholesterol and particle number.” Journal of clinical lipidology 5.2 (2011): 105-113.

[5] Meisinger, Christa, et al. “Plasma oxidized low-density lipoprotein, a strong predictor for acute coronary heart disease events in apparently healthy, middle-aged men from the general population.” Circulation 112.5 (2005): 651-657.

[6] Parthasarathy, Sampath, et al. “Oxidized low-density lipoprotein.” Free Radicals and Antioxidant Protocols. Humana Press, 2010. 403-417.

Isn't this why ketogenic diets also limit protein? I think you're right that if someone is eating a low-carb diet but also eating excessive protein, they wouldn't be adhering to an insulin-based theory.

Ketogenic diets seem best understood as diets that put fat intake as high as possible. Some protein intake is necessary, to obtain essential amino acids, but ideally not more than that. Carb intake can almost entirely be eliminated, because there are no essential carbs, and plant consumption can focus on low-carb plants (e.g. nuts, leafy greens).

I don't mean to endorse ketogenic diets, since I don't know whether they work. But they're at least internally consistent provided protein intake is also limited.

The keto diets most people follow are loaded with animal proteins and fats, although they don't have to be that way. There are some benefits to a healthy keto diet but there are also some serious risks, particularly in the longer term.

https://www.thepaleomom.com/adverse-reactions-to-ketogenic-d...

Exactly. The good old "eat less" diet works, but is not as sexy as all the fad ones.

So I can eat just cardboard, so long as I don't eat so much of it that I can't expend the energy?

It's nowhere near as simple as that.

You can eat whatever the hell you want, so long as you don't eat so much of it that you don't burn off the energy. It's precisely that simple.

Of course, you could say it's complex because you have to choose to reduce your energy intake, and the way that we make that choice is complex. But in that sense, everything is complex.

So all food/non-food is useful to the body in the same way? Just so long as you burn it off? Is all energy expenditure by the human body the same?

Micronutrients, obviously not. You have to get your required vitamins and minerals etc. or you'll get sick. But for macronutrients (basically carbs/fats) then yes, basically. Maybe you'll be slightly more or less efficient with some types of food, but in the end, if you eat a calorie you have to burn a calorie or you'll put on weight.

The key factor is to realise that it's relative to your body. Maybe for you, personally, a gram of fat is more efficiently metabolized than a gram of carbs. Whatever. You have to close the loop.

If you're above your target weight, eat progressively less until you start losing weight, then maintain that intake until your target weight. If you're below your target weight, eat progressively more until you're gaining weight, then maintain that intake until your target weight.

What if you're gaining fat instead of muscle? I think your version only works if the only metric required is purely -Kg over time, and doesn't factor in anything else that people might want to call it 'healthy weight loss/gain.'

OK, so which goalposts would you like us to aim for here? If you want to be healthy, eat a balanced diet. If you want weight loss, then eat less food than you burn, using a feedback loop to adjust our dietary intake. If you want fitness, do some cardio. If you want strength, lift some weights. If you want all of these things, then do all of these things.

The goalpost that is in some way meaningful, which adjusting total consumption of 'whatever' for the sake of purely moving a number up or down isn't.

For a given level of energy output, metabolizing fat requires more oxygen than metabolizing carbohydrates. There are some minor individual differences in efficiency but the basic relationship is true for everyone. That's why you don't see low-carb diets consumed by athletes who compete at the top levels of sports in which VO₂max is a limiting factor.

It's a bit surprising that the number of degrees burning your food will raise the temperature of water is related to weight gain. I find it more surprising that this simple relation has withstood the test of time.

Can’t tell if sarcastic or not. Burning food to release chemically stored energy therein seems like it would correlate naturally to the chemical energy an organism could extract.

Not at all sarcastic. I mean, we're told this process all the time so it seems like "duh", but if you really think about it there are lots of jumps and hand waving in that process.

For me, the easiest way to eat less calories is to eat a low-carb diet. The reason is this: my typical meal consists of three parts; meat, vegetable, and starch. The least healthy and highest calorie part is the starch. Cut the starch, cut most of the caloric intake.

Besides, if I cut enough carbs, I get into ketosis, and then I stop being hungry.

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