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RC Yu

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RC Yu•11 days ago

Can AI make scientific discoveries?

One thing I hear often is that "AI will help research, but it can't make original discoveries" (or some variant).

This article New ‘AI scientists’ are improving – but reveal their fundamental limits seems to say that LLM models can help research, but as they are based on language, they lack precision needed to validate fully hypothesis (and make discoveries on their own).

Surely this is all just a temporary limitation? Or is there some fundamental barrier?

(By the way check out credo summary of the article, which automatically pulls out the research papers cited!)

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The "carnivore diet" may promote weight loss, but risks nutrient deficiencies and high cholesterol.

Claim: The “Living Carnivore” Diet is Good for Weight Loss

Verdict: Broadly true, but misleading

“Within 30 days I lost 20 pounds. JD Vance is also on the diet and you can see how different he looks.”

“The way that you're supposed to eat it is bite for bite. You take a bite of the meat, you take a bite of the sauerkraut”

RFK Jr.

After Vice President JD Vance credited his weight loss to RFK Jr’s recommended “meat and sauerkraut” diet, the “Living Carnivore” diet has been under the spotlight. But does it really work?

The Good News: Weight Loss is Reasonable

For the goal of weight loss – without considering other issues – and despite no direct evidence on the Living Carnivore diet specifically, it doesn't seem too bad. This largely comes down to the benefits of eating fermented foods. Generally speaking, there are multiple benefits to consuming fermented foods, as shown by a study using data from the National Health and Nutrition Examination Survey (NHANES) from 2001 to 2018.

The study found that each 100 g of microbe-containing foods was associated with reduced BMI, waist circumference, systolic blood pressure, C-reactive protein, plasma glucose and triglyceride, and increased high density lipoprotein cholesterols. The mechanisms of action get a little complicated, but generally include influencing gene expression, slowing gastric emptying and modulation of the gut microbiome.

The carnivore side of the diet is where the problems come in. Purely for weight loss, there is some evidence that they can lead to weight loss and increased satiety.

The Bad News: Nutrient Deficiencies and Cholesterol

A 2026 scoping review focused on the carnivore diet noted these benefits for weight loss, but stressed the “substantial risks” of nutrient deficiencies. Overall, the carnivore diet can lead to deficiencies in thiamine, vitamin C, vitamin D, magnesium, iodine, potassium, calcium and fibre. The deficiency in fibre is also pretty extreme, at less than 1/25th of the adequate intake. It's debatable whether you could rectify these issues by adding fermented foods.

Perhaps unsurprisingly, low-density lipoprotein cholesterol and total cholesterol generally increase, carrying risks of heart disease, and some versions have high sodium, potentially leading to high blood pressure and more.

And it should go without saying that eating “bite for bite” is probably useless, it takes a long time to digest food, relative to actual eating process. It all hits your stomach basically simultaneously anyway.

Overall, the diet – especially fermented foods – could help weight loss, but it’s terrible as an overall diet.

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RC Yu•16 hours ago

Colonial German descendants: 2% of population, but own 70% of Namibian land?

Saw an Instagram post (by @AidanSimardone) with this claim, which caught my attention.

I guess one shouldn't be surprised by the abysmal lasting legacy of colonialism. But nonetheless I looked into the claim to learn more.

TLDR: the claim is an exaggeration/simplification, but the actual figures/stats are "still bad".

The first article I stumbled onto was this BBC article: "What's the right price to pay for genocide?".

It summarises Germany's brutal 1904-1908 colonial campaign in (present day) Namibia, noting:

As many as 65,000 of the 80,000 Herero living in German South West Africa at the start of colonial rule are estimated to have perished, as well as perhaps 10,000 of an estimated 20,000 Nama.

and the two countries' efforts to account for it:

Since 2015, when Germany formally acknowledged that the atrocities constituted genocide, it has been negotiating a restorative justice deal with Namibia that will set a global precedent.

On the 70% land figure, the article highlights the historical land distribution/seizure:

... most of their land was split into private farms for German settlers. And today most Herero and Nama live either on small overcrowded areas of communal land that were later allocated to them ... .

and specifically on today's ownership:

German Namibians are believed to be the biggest group among the white farmers who own about 70% of the country's farmland.

So according to the article, it's not exactly 70% of all land, but 70% of farmland. And it's not "white Germans" only, but they are the biggest group.

So the original claim is off, but the sentiment remains.

So what are the actual numbers?

I found this piece by "Namibia Fact Check" (an initiative by a Namibian think tank) – that did the math based on Namibia Statistics Agency (NSA) data:

  1. It states "previously advantaged farmers" own ~70% of commercial (freehold) farmland.

  2. The piece says "Previously advantaged farmers" isn't strictly speaking "white Germans", and says it's not clear what percentage of the population they make up (but it sounds like that data isn't officially available, and it is understood to mean white Germans and South Africans pretty much. From googling it sounds like white make up ~2-6%).

And commercial (freehold) farmland constitutes ~42% of total land surface.

And so, "previously advantaged farmers" (basically white Germans and South Africans, that make up 2-6% of the population) own ~a third of total land (70% x 42%).

So yes, the original claim seems to be an exaggeration – but the sentiment remains. The actual figures aren't exactly rosey.

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RC Yu•7 days ago

Politics of transboundary haze in Southeast Asia

Seasonal haze has gone on for decades. I'm interested in digging into the politics of haze

Why has Indonesia not been able to stop illegal forest burning? Why has regional pressure not worked?

Here's one paper to start with, that found:

The study reveals a significant electoral cycle (a repeated pattern linked to elections) in forest fires. Both the number of ignitions and the area burned decline during election years. They then increase steeply in the year after elections. The authors argue that politicians may suppress forest burning when it could damage their electoral chances. After elections, those incentives weaken, allowing more burning for land conversion.

I find this somewhat encouraging -- as it suggests that forest burning can be reduced, when political incentives align.

The challenge is how to align incentives more permanently -- beyond the narrow pre-election period.

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RC Yu•4 days ago

Informative post on arsenic and rice. Here's a paper shared with specific recommendations on how much rice kids should eat:

To avoid a risk of developing cancer, infants up to one year of age should consume no more than 32.2 g of the studied products per week, children under three years of age up to 68.7 g, and adults 243 g.

So infants should eat less than a bowl of (white) rice a week.

Arsenic in Brown and White Rice

I recently added more rice into my diet and wanted to understand the nutritional value of switching from white to brown rice. Then I recalled hearing about the potential risk of more arsenic so I dug into the research.


This 2016 risk assessment from the FDA provided baseline numbers of the amount of arsenic in rice and rice products as well as a quantitative estimate of lung and bladder cancer risk from long-term exposure of these products.

We found that average concentrations of inorganic arsenic – the more toxic form of arsenic – were as follows:

• 92 parts per billion (ppb) in white rice

• 154 ppb in brown rice

• 104 ppb in infants’ dry white-rice cereal

• 119 ppb in infants’ dry brown-rice cereal

The primary culprit of damage is inorganic arsenic in foods, which I learned in not a traditional heavy metal but a "toxic metalloid". The good news is this means inorganic arsenic doesn't bioaccumulate the same way other heavy metals do. The risk however is still continuous exposure over a long period of time which can damage DNA, the skin, and the vascular system.

Dr. Michael Greger also provides a good summary and insights in his video

Which Rice Has Less Arsenic: Black, Brown, Red, White or Wild?Evaluating differences in rice, we can observe:

  • brown rice contains more arsenic than white rice

  • long grain contains more than shorter grains, though this may be due more to where these grains are grown

  • arsenic accumulates in the rice bran, which is why brown rice contain so much more arsenic

  • many of the varieties of colored rice were worse than white rice for the reason above

  • children under 6 should almost definitely avoid rice AND rice products, with regulations in the EU now adding more conservative limits on the amount of acceptable arsenic in rice products for infants

One bit of good news is brown rice MAY make the arsenic less bio-available as shown in this population study. As Dr. Greger says:

So, if you test the urine of thousands of Americans who don’t eat rice at all, they’re still peeing out about eight micrograms of toxic, carcinogenic arsenic a day. It’s in the air; it’s in the water; there’s a little bit in nearly all foods. But, eat just one food—a cup or more of white rice a day—and your exposure shoots up 65%.

Okay. But, what about those who eat a cup or more a day of brown rice, which technically contains even more arsenic? Your exposure shoots up the same 65%. No difference between the urine arsenic levels of white rice-eaters compared to brown rice-eaters. Now, this was not an interventional study, where they feed people the same amount of rice to see what happened, which would have been ideal. This was a population study. So, maybe the reason the levels are the same is that white rice-eaters eat more rice than brown rice-eaters. So, that’s why they ended up with the same levels? We don’t know, but it should help to put the minds of brown rice-eaters at rest.

So what is the risk? This analysis from the EPA used a Bayesian approach to estimate the dose response of inorganic arsenic exposure from water. It found a linear relationship of more arsenic exposure with bladder and lung cancer. If we extrapolate the EPA's 2025 upper-bound estimate: one daily cup of brown rice for life adds up to 0.42 percentage points of bladder or lung cancer risk (+5.5% relative to a 7.6% baseline); white adds 0.25 (+3%). At three cups: 1.45 (+19%) for brown and 0.8 (+10%) for white.

A more direct causal study would need to prove out this relationship, but this definitely took me aback. For rice staple cultures, three cups of rice daily is pretty normal. These upper bound figures begin to look similar to increased risk of cancer from a daily beer or alcoholic drink.

Unfortunately rinsing rice does little to remove arsenic, especially in brown rice. But researchers did find a parboil method could dramatically reduce the amount of arsenic, removing 54% & 73% iAs from brown & white rice. This is a specific method that requires a lot water that is then tossed out but it does retain a lot of the same nutrients.

My takeaway? We are exposed to arsenic across a number of ways; through our air, water, and food. The increased cancer risks are linear from continued exposure, which means the amount of arsenic consumption scales with risk. If I was a regulatory body in a country where rice is a staple food, I would set significantly stricter regulations to evaluate and limit the amounts in rice and rice products.

Personally, it doesn't seem worth eating rice regularly, especially brown rice. I'll probably try to have less than 3 to 4 servings a week and mix in other grains. I'd be especially careful with infants and rice products that may concentrate the arsenic levels.

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RC Yu•9 days ago

AI companions and loneliness

This is an interesting piece by a Malaysian think tank, that covers the use of "ai companions" and loneliness.

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RC Yu•24 days ago
Parentingscreen time

Is "screen time" bad?

As a parent, I wonder if screen time is bad. I came across this study, that seems to be widely debated.

The study basically analysed some large datasets, to examine whether screen time negatively affected teens (controlling for various factors).

What they found: basically almost no effect.

Caveats:

  • "screen time" is a huge category: it could include social media doomscrolling, but it could also include doing homework on a computer.

  • also, the study didn’t separate how screen time may affect different teens differently (e.g. boy vs girl, different ages).

Subsequent papers have delved deeper, and indeed found not all screen time is harmless.

Thoughts:

  1. screen time per se is not necessarily good or bad. We need to look into the specific screen activity.

  2. I still worry about eye sight though (kids staring at screens will have worse eyesight?). Need to explore more papers!

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RC Yu•11 days ago

New research on teen lonelines in Malaysia

Interesting new study by Tan Heang-Lee and Farah Nabilah (ISIS Malaysia): Lonely by design.

It covers a unique angle, examining possible relationships between AI companions and loneliness:

This research note examines how social media and AI companions may deepen loneliness among Malaysian adolescents by replacing meaningful connection with performance, comparison, and low-risk artificial companionship. It highlights the links between loneliness, mental health, social development, and broader social cohesion, and calls for safer technology and stronger opportunities for in-person belonging.

(from the credo summary)

I've heard a lot about social media and mental health effects, but not about AI companion use.

We need to be getting ahead of this technology use and it's impact on children (and society generally), so good to see this research.

The study makes recommendations including:

enforcing provisions on manipulative design features, extending school recess and providing green spaces in neighbourhoods.

(from the report executive summary)

I believe the researchers are going to conduct follow up, primary research -- so watch their space!

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Hot drinks cause cancer

Saw this really interesting article in The Guardian, about a new study linking hot drinks with esophagus cancer.

Apparently this link (between hot drinks and cancer) had already been suspected, as this 2016 WHO note highlights.

Anyway, this is the latest 2026 study that the Guardian article spotlights.

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Does flying increase cancer risk?

Going on a tangent from another Board. We were talking about "space weather" and landed on the question of "flying and radiation".

Found this literature review found that:

aircrew have higher rates of certain cancers, such as melanoma, non-melanoma skin cancer, and breast cancer in female flight attendants, compared to the general population. However, the evidence does not clearly prove that cosmic ionizing radiation alone causes these cancers, because other factors—like disrupted sleep patterns, lifestyle, and exposure to chemicals—also affect risk.

(Quoting the Credo summary)

To me, it sounds plausible. Flight attendants, pilots, and frequent flyers beware!

StarTalk Show Notes•a month ago
StarTalkspace weather

Season 17, Episode 48: 3 Ways Space Weather (Possibly) Impacts Your Everyday Life

Hey StarTalkians! Season 17, episode 48 was a sit-down discussion with Neil, Chuck and guest Dr. Lika Guhathakurta, a heliophysicist at NASA. The latter half addressed space weather, coronal mass ejections and the many ways in which the sun can – and does – impact our lives.

Super Solar Storms with Lika Guhathakurta - StarTalk Radio

One of Dr. Guhathakurta’s papers delves into what she calls “everyday” space weather, and overlaps with a lot of the podcast discussion.

Carrington-Like Events

Around 50 minutes into the show, they discuss the so-called “Carrington Event” of 1859, and Dr. Guhathakurta also covers this issue in the paper mentioned above. But as her paper points out, there have been others.

A 1989 space weather event knocked out transformers in New Jersey, the United Kingdom and Quebec, with Quebec also losing power for 9 hours. In 2003, geomagnetic storms caused blackouts in southern Sweden and possibly damaged transformers in South Africa.

3 Everyday Effects of Space Weather

Those events are more dramatic – thankfully, we don’t have that type of thing every day. However, that doesn’t mean space weather doesn’t have everyday impacts.

1: Power Problems

It doesn’t have to be a Carrington-like event for space weather to impact your electricity supply. A paper referenced by Dr. Guhathakurta looked at data on insurance claims for industrial electrical equipment, cross-referenced with space weather conditions. While they struggle to pin down a precise dollar amount for the cost – it’s probably in the billions – they calculate that 500 claims are submitted in the US annually because of space weather.

2: Cosmic Rays During Flights

When you travel by plane, you’re exposed to more cosmic rays – high-energy particles originating in distant events like supernovae. At solar maximum, the sun’s magnetic field actually protects us, but at times of lower solar activity, we’re exposed to more. A study looking at this calculated that flying at high latitudes for 12 and a half hours exposes you to as much radiation as a chest X-ray, or about half that for mid-latitudes.

3: The “Blurry Vision” of Your Satellite Navigation

Dr. Guhathakurta estimates [2] that about a third of the inaccuracy of satellite navigation devices come down to space weather. Irregularities in the ionosphere can refract and scatter their signals, leading to what she calls “blurry vision.” It isn’t a huge effect, but it is definitely something you’ll notice often!  

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