Tired After the Time Change? A Fall-Back Energy Plan With BHB

Clocks fell back one hour at 2 a.m. this past Sunday, November 1, and if you feel more wiped out this week than the “extra hour of sleep” promised, you have company. Feeling tired after the time change is common, and it has less to do with how many hours you slept Saturday night than with your body clock running an hour ahead of the one on your wall.

Here in Denver the sun now sets before 5 p.m. That early darkness, plus mornings where you’re wide awake at 5, is what throws people off. Below is what sleep researchers say, a simple plan, and where caffeine and goBHB® fit.

Why You Feel Tired After the Time Change

Your internal clock is set mostly by light. When the social clock jumps but the sun doesn’t, the two drift out of sync until your body catches up. The American Academy of Sleep Medicine describes exactly this in its 2024 position statement: the yearly change between standard and daylight saving time creates a misalignment between your circadian rhythm and your schedule, and that misalignment has been associated with risks to health and safety. The AASM’s position is that the U.S. should drop the switching altogether and stay on permanent standard time, which it says lines up best with human biology.

The fall change is generally considered the gentler of the two, since you gain an hour instead of losing one. It still causes problems. Your body wakes up at what it thinks is 6 a.m. when the clock says 5, you’re dragging by mid-afternoon, and the dark at dinnertime makes you want to crash at 8. Then you reach for a late coffee to push through.

The Afternoon Coffee Trap

When the afternoon slump hits harder than usual, most people reach for caffeine, and caffeine’s effect on sleep lasts longer than people think. In a small 2013 randomized trial (12 people) in the Journal of Clinical Sleep Medicine, Christopher Drake and colleagues gave 400 mg of caffeine at bedtime, 3 hours before bed, or 6 hours before bed. All three timings significantly disrupted sleep compared with placebo, and the authors concluded people should avoid substantial caffeine for at least 6 hours before bed.

Do the math for a 10 p.m. bedtime and your caffeine cutoff is 4 p.m. That’s right when the new early sunset makes you feel like the day is over. A 4:30 energy drink feels like a fix, but it costs you sleep that night and leaves you more tired the next afternoon.

Three timing numbers from the research

Hours, from two published human studies. These measure different things.

D-BHB back to baseline after a ketone salt drink3 to 4 hLongest caffeine gap tested (400 mg); sleep still disrupted6 h before bedL-BHB still above baseline after a ketone salt drinkmore than 8 h

Bar length = hours / 8. The L-BHB bar is a minimum (gone by 24 h). BHB values come from drinks with about 12 to 24 g of BHB salts, not goBHB product doses. The caffeine bar is a sleep-disruption timing, not a blood level. Sources: Stubbs et al., Front Physiol 2017; Drake et al., J Clin Sleep Med 2013.

A Simple Plan If You’re Tired After the Time Change

Get light later in the day

Light is the strongest signal your clock gets. After falling back, your clock needs to shift later, and late-afternoon and early-evening light pushes it that way while very early morning light pulls it earlier. If you wake at 5, keep the lights low until your normal wake time, then get outside.

Move bedtime gradually

If you’re waking at 5 a.m., push bedtime 15 to 20 minutes later each night instead of forcing an hour on day one. Keep wake time consistent, weekends included.

Set a caffeine cutoff and keep it

Pick a hard stop 6 hours before bed based on the Drake data. If you need something in the afternoon, use something without a stimulant.

Where goBHB Fits

BHB (beta-hydroxybutyrate) is the ketone your body makes when you fast or cut carbs, and goBHB delivers it directly. It isn’t a stimulant, and it won’t reset your body clock. It is a caffeine-free alternative if you’d otherwise reach for a stimulant, and there’s early human research on BHB taken at night.

The sleep study

In a 2025 randomized, double-blind trial published in Bioscience, Biotechnology, and Biochemistry, 90 healthy Japanese adults with fatigue and below-par sleep scores took 1.5 g of D-BHB, 2.9 g of D-BHB, or a placebo drink before bed for 14 days. Compared with placebo, both doses improved scores for sleepiness on rising. The 1.5 g dose also improved initiation and maintenance of sleep, and the 2.9 g dose improved feeling refreshed on rising. Total sleep length did not change. The sleep measures were questionnaires, the groups had 30 people each, and the study was funded by Osaka Gas, which makes the D-BHB used. I’d call it promising, not proven, and we cover it in more depth in our ketones and sleep review.

How long BHB lasts, and why the form matters

A University of Oxford study in Frontiers in Physiology (Stubbs 2017) gave volunteers drinks with roughly 12 to 24 g of sodium plus potassium BHB salts and found blood D-BHB returned to baseline within 3 to 4 hours. The L-BHB half of those salts stayed above baseline for more than 8 hours. That’s relevant because the sleep trial used pure D-BHB. I’m not aware of any published trial testing L-BHB at bedtime, or whether L-BHB in the blood affects sleep at all. To be conservative with an L-BHB product, I’d take it by early afternoon. Our post on the best time to take BHB covers timing for each goal.

Which goBHB Product for Which Part of the Day

Morning: MAC Energy

MAC Energy: 2,000 mg goBHB plus 200 mg caffeine per 12 oz can.

If you want caffeine, take it early. MAC Energy pairs 2,000 mg of goBHB with 200 mg of caffeine from PurCaf® and 250 mg of Cognizin® citicoline, with zero sugar and 10 calories per can. It comes as a 12-pack for $29.99 on drinkmac.com in four flavors. Drink it in the morning, not at 4 p.m., and count its 200 mg toward your total caffeine for the day, coffee included. If you’re sensitive to caffeine, under 18, pregnant or nursing, or on medication that interacts with stimulants, skip it.

Early afternoon: CleanForm goBHB Energy Shot

CleanForm goBHB Energy Shot: L-goBHB, zero caffeine, zero sugar.

For the early-afternoon slump, the CleanForm goBHB Energy Shot is the caffeine-free option. It’s a 2 oz shot built on L-goBHB® with no caffeine or sugar, sold as a 6-pack for $29.99 in Blue Raspberry, Wild Berry and Sour Apple, and it’s TruShield Certified for banned substances. Because L-BHB lingers longer in the blood, I’d take it by about 2 p.m. rather than later in the day.

Where the Evidence Stands

The circadian side is well supported. The AASM says the seasonal switch throws your clock off, and the caffeine timing data comes from a randomized trial. The BHB side is earlier. One industry-funded trial found 14 days of D-BHB before bed improved how people rated their sleep and mornings, with no change in sleep length. Our own cell work on BHB and the caffeine crash is unpublished lab research, not a human result. I’m not aware of any study of BHB specifically for the clock change, so take this as a sensible way to use it, not a tested protocol. BHB salts also add sodium and other minerals, so if you have blood pressure or kidney concerns, are pregnant, or take medication, check with your doctor first.

FAQ

Why am I so tired after the clocks go back?

Your body clock is still running on the old time, so you wake earlier, fade earlier, and feel the early darkness at dinner. Sleep researchers, including the AASM, describe the switch as putting your internal clock out of step with the clock on the wall.

How long does it take to adjust to the time change?

It varies. Consistent wake times and late-day light speed it up, and shifting bedtime 15 to 20 minutes a night lets your clock catch up without forcing it.

Is it OK to drink coffee in the afternoon after the time change?

In a randomized trial, 400 mg of caffeine disrupted sleep even when taken 6 hours before bed. Set your cutoff at least 6 hours before bedtime and use a caffeine-free option after that.

Can BHB help you sleep better?

One 2025 trial found 1.5 g or 2.9 g of D-BHB before bed for 14 days improved self-rated morning sleepiness compared with placebo. It’s a single small, industry-funded study, so the evidence is early.

The Bottom Line

Feeling tired after the time change comes down to your body clock lagging the wall clock. Get light in the late afternoon, ease bedtime later, stop caffeine at least 6 hours before bed, and give it a week. If you use goBHB, put the caffeinated version (MAC Energy) in your morning and the caffeine-free shot by early afternoon, and keep expectations in line with what the research has actually tested.

Disclosure: goBHB Labs makes goBHB® and L-goBHB®, the BHB in MAC Energy and the CleanForm goBHB Energy Shot, and benefits from their sales.

Sources: Rishi MA, et al. Permanent standard time is the optimal choice for health and safety: an American Academy of Sleep Medicine position statement. J Clin Sleep Med. 2024;20(1):121-125. Drake C, et al. Caffeine effects on sleep taken 0, 3, or 6 hours before going to bed. J Clin Sleep Med. 2013;9(11):1195-1200. Katsuya S, et al. Effect of d-β-hydroxybutyrate on sleep quality in healthy participants. Biosci Biotechnol Biochem. 2025;89(5):769-775 (funded by Osaka Gas). Stubbs BJ, et al. On the Metabolism of Exogenous Ketones in Humans. Front Physiol. 2017;8:848. goBHB Labs internal cell study: BHB and the caffeine crash (unpublished). Product details from drinkmac.com and cleanformnutrition.com.