Downsides of High Carb (and/or High Protein Diets) on Brain Health?

I hear that eating “too much” carbs can cause diabetes, Alzheimer’s, and dementia, or at least increase your chances of getting them or speeding up the onset:

This could possibly due to the sugar created by the carbs affecting the brain, in the case of alzheimers and dementia?

Although, there are some reports that high protein diets can be bad for preventing alzheimers and dementia:

One consistency seems to be that high-fat diets can help with alzheimers and dementia.

So where does Huel fall into all this?

Huel seems to be high protein and high carb.

If one ate 2,000 kcal of Huel a day (and nothing else) of Vanilla Huel they’d get:

  • Fat: 64g

  • Carbs: 190g

  • Protein: 145g

Personally, I would eat at least 2,500 kcal of Huel per day, so would get at least:

  • Fat: 80g

  • Carbs: 237.5g

  • Protein: 181.25g

Are these amounts pushing me into the danger zone in regards to diabetes, dementia, etc?

Would I be eating a high-carb diet?

Would it be better to aim for 2000 kcal of Huel White per day, so that I hit my 100% RDA of vitamins etc, then for my other meals, have Black to keep the carbs down?

Thanks for reading!

High sugary carbs = bad.

High low-GI carbs = good.

Huel has low-GI carbs.

High animal-protein = bad.

High plant-based protein = so far evidence says good.

Huel has plant-based protein.

High oxidized fats (especially omegas), often from fish = bad.

High non-oxidized fats (with good ratio of omegas, and unsaturated in general) = good.

Huel’s source of fats is not prone to much oxidation, and Huel has good amount of unsaturated fats.

Hence Huel fits into the category where all is good (so far according to evidence). Important addendum: very few studies have looked at plant-based sources of fats/proteins and low-GI carbs, because nobody (aside from people who eat future foods like Huel) eats that way (not even vegans commonly).


It’s also important to note that one can only consume so many calories in a day. Hence if one has a diet consisting predominantly of carbs, they might end up missing out on some vitamins&minerals or might not have sufficient protein or fats. Similar case when one’s diet is high in protein and fats - they might also miss out on some micronutrients. Huel provides everything your body needs (at 2000kcal/day) hence none of these concerns exist, and unfortunately none of the studies apply.


Great post, rikefrejut. I think it’s also important to contextualise ‘high’ when we say ‘high carb’ or ‘high protein’. All your calories are going to come from a mix of carbohydrates, protein, fat and alcohol. Huel is 40% carbohydrate, 30% protein and 30% fat. Is that high carb? High protein? High fat? The OP describes it as high protein and high carb, but what cut-offs are being used and why?

Macro ratios in traditional diets vary pretty widely, but I think it’s pretty common to see 70–80% carbs throughout history. The typical American diet is more like 50/15/35. Huel is lower in carbohydrates, relatively, than the majority of traditional diets. Important to keep in mind that diet plans like Atkins and keto are extreme, and not following them isn’t ‘high carb’. By default if you say high carb I’m thinking 70–80%.

As for protein, Huel is definitely high protein, and Black even more so. My understanding is that 10% is the minimum, and the body of evidence is that there’s benefit to increasing that into the 20–30% range. I also read too much protein is definitely bad for you, at around 40% or higher.

Anyway, the first study link I can’t access and the abstract doesn’t give context I can work with. The second link doesn’t give numbers, but cites the Mediterranaean diet as a good diet for the purposes of being higher in fat and lower in carbohydrates than some baseline. The typical Mediterranean diet’s macro ratio isn’t far off Huel: main difference is Huel is higher in protein.

The third link is about a study on mice, so while it has context of numbers they include values like 5% protein (which would be serious deficiency for a human). It again cites the Mediterranean diet as being the answer, calling it low protein, which… it isn’t. Read enough of these and you get the distinct impression many authors simply hold the value that the Mediterranean diet is the answer, whatever the question is!

Honestly, this is all extremely complex. One study here or there won’t overturn the whole balance of research. Huel has a pretty conservative macro ratio. The one key question I hope Huel continue to look at is it the body of evidence on optimal protein intake, and sure, maybe it will shift in time to suggest less than 30% would be better.

Is that all animal protein, including steaks? Or just highly processed animal protein?

The evidence is mixed so far. It is a definite yes, highly processed animal protein is bad. For other meat, it seems to depend on many factors including the quality of the meat (most meat is bad quality) and how it is prepared (boiling appears to be the only safe one where you don’t get much production of carcinogenic substances).

Trouble is almost everyone either eats highly processed meat, or bad quality fried meat - for taste reasons. I highly doubt people could be convinced to pay 10x the price for good meat (I am not joking, it really is an order of magnitude difference in cost) and then boil it (which will destroy the flavor that people enjoy).

Here are some articles about how healthy certain meats are. Perhaps these would be worth a read. I’ve provided excerpts from the summary/bottom line part of these articles. It seems white meat is the healthiest, red meat is generally fine, and processed meat is a big no-no.

“To maximize benefits and minimize risk, choose non-processed meat, avoid high-heat cooking, include plant foods in your diet, and choose organic or grass-fed whenever possible.”

“Unprocessed and properly cooked meat has many nutrients and may have some health benefits. If you enjoy eating meat, there is no compelling health or nutritional reason to stop.”

“As long as you choose unprocessed and preferably grass-fed red meat, make sure to use gentler cooking methods and avoid burnt/charred pieces, there probably is nothing to worry about.”

“Properly cooked red meat is likely very healthy. It’s highly nutritious and loaded with healthy proteins, healthy fats, vitamins and minerals, along with various nutrients known to positively affect the function of both your body and brain.”

The increased risk, if it’s found in a study, is very, very small. I wouldn’t worry about this at all and as others have said “carbs” is a huge category. For overall health stick to wholegrains and unrefined carbohydrates which provide fibre, vitamins and minerals as well as complex carbohydrates.

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That’s useful, thanks! What are your thoughts about this article? Body Recomposition for Women: Lose Fat and Gain Muscle — Unimeal is it possible?

Thanks for sharing @kartidaan

In general, it’s quite hard to lose fat and gain muscle at the same time which is why you often hear about shredding and bulking phases.

I like the article as a whole and think it provides some good advice so I’ll just pick out the bits it falls short.

  1. No need to calorie cycle and overcomplicate things.

Most people look at calorie deficit as a daily thing as that’s easy to track but it’s also helpful to view it on a weekly and monthly basis. This is why some people struggle to lose weight as they follow a calorie deficit plan during weekdays and then at the weekend eat what they like and it balances out to them not being in a calorie deficit across the whole week.

  1. “Some studies also show that too high protein intake can lead to kidney stones and other health problems”

Unless you have problems with your kidneys or have been advised by your doctor to follow a reduced protein diet, ignore this.

If you browse pubmed you will always find an article that found an association between every bad diagnosis you can imagine and some kind of diet, lifestyle, food or whatever you want.

I think it is more helpful to keep a balanced way of living. Trying things out, seeing what makes you feel good and what works for you. Breathing and cellular metabolism, that is living, creates free radicals. Reason enough to stop it? I don’t think so.

And keep in mind: Too much mental stress and worrying might also accelerate aging on all levels - and increase the risk of various diseases.

Anyway - Huel is balanced nutrition. Maybe a bit higher in protein than standard diets, but no diet conforms 100% to “official recommendations” - which can also be questioned.

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