Cheese Nightmares, NAD+ Lies, Fast-Forward Learning

Howdy readers 👋 Signals coming at you a day early (Happy 4th of July 🇺🇸). If you're hosting tomorrow’s BBQ, maybe hold off on the cheese (it could be causing your nightmares). Also, is watching YouTube at 3x actually making you smarter? And you can’t trust what's in your supplements…

Cheese may really be giving you nightmares.

Turns out, lactose intolerance could be behind your nightmares. Scientists have found that nightmare severity is robustly associated with lactose intolerance and other food allergies [the article]. Participants who also ate healthier evening meals had better sleep and fewer nightmares.

Our take: Even if cheese isn't directly causing your nightmares, eating close to bedtime can raise your core body temperature and trigger sympathetic nervous system activation, which may reduce deep-sleep quality. Aim to finish your last meal at least three hours before bed. Also, the study’s link with healthier evening meals = better sleep might actually reflect an overall healthier lifestyle rather than just diet alone.

You really want to try anything to avoid frequent nightmares or disturbed sleep, as frequent nightmares significantly accelerate biological ageing and increase the risk of premature death by nearly three times [the study]. - Tash J (Newsletter Nerd, Superpower)

Supplement label lies about popular NAD+ products

Independent lab testing commissioned by ChromaDex (the makers of Tru Niagen) found that over half of the top-selling NAD+ supplements on Amazon contained less than 1% of their claimed active ingredient and many had none at all [the analysis]. Softgels and “liposomal” formulas were the most likely to underdeliver. Among nicotinamide riboside (NR) supplements specifically, 74% fell dramatically short of their label claims.

This isn’t just about NAD+. ConsumerLab also flagged widespread quality issues across anti-aging and longevity supplements in a March 2025 report [the report]. Poor labeling, unverified claims, and fake Amazon listings are disturbingly common.

Our take: Don’t trust flashy packaging or big claims. Choose supplements that publish third-party test results, and buy directly from trusted sources or vetted platforms (like the Superpower Marketplace, obviously!). Look for brands that use USP, NSF, or Informed Choice testing - and skip liposomal formulas unless the brand provides data to back them up.

Partly because:

• Amazon does not independently verify ingredients for third-party supplements.

• Liposomal and softgel forms are harder to test and often have lower stability.

• Unlike drugs, U.S. supplements are not required to prove efficacy or purity before sale.

• A company can choose to pay for third-party testing.

• NAD+ precursors (especially NR and NMN) are highly unstable, especially in softgel/liquid form unless stabilized.

-Julija Rabcuka, (Clinical Strategy, Superpower, BA (Oxon), MSc, PhD (ABD), University of Oxford)

What happens to your brain when you watch videos at 1.5x speed

A recent analysis found that watching online videos at faster playback speeds (1.5x or more) negatively impacts your ability to retain information [the meta analysis]. At moderate speeds (1.5x), memory performance slightly drops, but at higher speeds (2x or faster), the effect becomes significant.

It remains unclear if regularly viewing at high speeds can help the brain adapt, or if it causes long-term cognitive effects. Additionally, faster playback can make viewing less enjoyable, potentially reducing motivation to learn.

Our take: I’m so tired of people bragging about listening/watching stuff on 1.2-3x speed. I personally do 1.2x but that’s because audible books tend to be a little slow.

When did information efficiency become the metric of success? Im totally in agreement on the lack of retention at those speeds. I think 1.2-1.3x is the sweet spot. - Ajay P (Head of Growth, Superpower)

Superpowered by you: Daily coffee consumption.

You might have seen “coffee drinkers are biologically younger” floating around on social media this week (check Dr. Rhonda Patrick’s IG post.) Before you start downing 3+ cups a day in pursuit of eternal youth, here are a few key things to keep in mind:

• Time your caffeine intake wisely. Aim to drink your coffee at least 10 hours before bedtime. This strategy maximizes the benefits of caffeine while minimizing the risk of sleep disruption.

• Choose roasts rich in polyphenols. Opt for light to medium roasts, as darker roasts can degrade antioxidants. Additionally, select beans grown at high altitudes in volcanic soil (regions like Ethiopia, Guatemala, and Costa Rica are excellent choices).

• Brewing method matters. Using a paper filter (think pour-over, batch brew, etc.) is the healthiest option, as it removes diterpenes, compounds that can raise cholesterol levels (we published a deep-dive on this a few weeks ago).

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That’s all for this week 🫡 Have a great 4th of July weekend!

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