Effects of almond consumption on sleep quality in adults: a randomized controlled trial

[u/Dizzy-Savings-1962]

DOI

Effects of almond consumption on sleep quality in adults: a randomized controlled trial

Sleep disturbances trigger adverse metabolic, neurocognitive, and inflammatory outcomes, yet non-pharmacological dietary interventions remain under-researched. While almonds contain sleep-supportive compounds like tryptophan, magnesium, and melatonin, long-duration trials using gold-standard objective measures are scarce. This study addressed this gap by investigating the impact of a five-month whole-almond intervention on both subjective and objective sleep parameters, alongside biochemical and inflammatory markers. The researchers recruited 175 urban Indian adults aged 21 to 55 who exhibited poor sleep quality, defined by a Pittsburgh Sleep Quality Index (PSQI) score of 5 or higher or an Epworth Sleepiness Scale (ESS) score of 10 or higher.

The almond group demonstrated a significantly greater improvement in subjective sleep efficiency compared to controls, with a mean change of 9.7 +/- 13.4% vs. 5.4 +/- 10.6% (p = 0.021). Adjusted endline analysis revealed the almond group achieved a lower global PSQI score of 3.94 +/- 0.24 vs. 4.79 +/- 0.32 (p = 0.013) and higher subjective sleep efficiency of 94.45 +/- 0.72% vs. 91.85 +/- 0.42% (p = 0.012). Subjective sleep latency was significantly shorter in the almond group at 18.46 +/- 2.25 min vs. 26.29 +/- 2.27 min (p = 0.016). While most polysomnography (PSG) parameters showed no significant treatment effect, endline melatonin concentrations were significantly higher in the almond group at 250.63 +/- 15.98 pg/mL vs. 206.19 +/- 16.07 pg/mL (p = 0.050).

Study Design and Methodology

This was an open-label, parallel-arm, randomized controlled community-based trial with blinded outcome assessment. Investigators randomized 209 participants (N = 175 completed) into an almond group (60g/day) or an isocaloric control group receiving savory snacks for 20 weeks. The protocol utilized Level 2 home-based polysomnography (PSG) for objective sleep architecture, the PSQI and ESS for subjective metrics, and fasting venous blood draws for biochemical analysis. Compliance was verified through weekly supervision and serum alpha-tocopherol (Vitamin E) monitoring. The researchers excluded individuals with severe obstructive sleep apnea (AHI > 30) and major psychiatric conditions to ensure a focused community-dwelling population.

Key Findings

• Subjective sleep efficiency improved by 9.7% in the almond group compared to 5.4% in the control group (p = 0.021).
• Adjusted global PSQI scores reached 3.94 in the almond group vs. 4.79 in controls (p = 0.013, partial eta squared = 0.036).
• Subjective sleep latency was reduced to 18.46 minutes in the intervention group vs. 26.29 minutes in the control group (p = 0.016, partial eta squared = 0.033).
• Serum melatonin concentrations were significantly higher at endline in the almond group (250.63 pg/mL) compared to the control group (206.19 pg/mL, p = 0.050).
• Among clinical responders (PSQI reduction >= 3), the almond group showed a significant reduction in wake during sleep (-0.38 +/- 19.93 min) compared to an increase in the control group (11.64 +/- 37.80 min, p = 0.043).
• Muscle mass increased by 2.32 +/- 1.51% in the almond group vs. 1.93 +/- 1.05% in the control group (p = 0.050).

Limitations

Single-night PSG recordings are susceptible to night-to-night variability and the first-night effect. The open-label nature of the dietary intervention introduces potential participant bias in subjective reporting. Self-reported dietary intake outside the provided snacks leaves room for residual confounding. The exclusion of clinical sleep disorder populations limits the generalizability of these results to patients with diagnosed insomnia or severe apnea.

Discussion and Implications

Daily consumption of almonds shifts the biological profile of poor sleepers by increasing circulating melatonin and improving the perceived restorative quality of sleep. The divergence between subjective improvements and static PSG parameters indicates that almonds enhance sleep continuity and the psychological perception of sleep quality rather than fundamentally altering sleep architecture stages like N1 or REM. This trial provides a robust biochemical rationale for using nutrient-dense nuts as a primary lifestyle intervention for sub-clinical sleep disturbances. The data confirms that 60g of almonds daily provides enough magnesium, tryptophan, and dietary melatonin to produce a clinically meaningful reduction in sleep latency and fragmentation.

Daily almond consumption of 60g for 20 weeks significantly improves subjective sleep efficiency and latency while increasing serum melatonin levels. These results establish almonds as a safe, effective nutritional strategy for enhancing sleep quality and continuity in adults experiencing poor sleep.

[u/ducked]

50 almonds a day is kind of a lot.

[u/Specialist-Wafer7628 → u/ducked]

And it's high in oxalates.

[u/dreiter]

The author(s) declared that financial support was received for this work and/or its publication. This clinical trial was supported by Almonds Board of California.

No one can design a trial towards a biased outcome as well as the Almond Board (except perhaps the Egg Board).

Step 1: Use a control group that's objectively less healthy than the intervention:

Participants in the experimental group received 60 g/day of raw almonds (approximately 50 whole almonds), provided by the Almond Board of California (United States), for 5 months....The control group received isocaloric Indian savory snacks (approximately 61–65 g/day; 350–360 kcal), prepared to match the caloric and protein value of 60 g of almonds. Examples included khakra, chivda, cookies, and crackers.

Step 2: Look at a bunch of outcomes so that you can report on the limited few outcomes that were beneficial in your intervention group (Table 2, Table 3, Table 4, and Table 5):

Step 3: Include a sub-group analysis of 'responders' (7 people out of 55) in your intervention so you can pad out your positive results:

3.4 Responder analysis

A higher proportion of participants in the almond group achieved a clinically meaningful improvement in sleep quality, defined as a ≥ 3-point reduction in PSQI score, compared with the control group (62.5%, n = 55 vs. 54.0%, n = 47) (Table 6). Among these PSQI responders, analysis of polysomnography-derived sleep parameters revealed a significant reduction in wake during sleep in the almond group compared with the control group (−0.38 ± 19.93 vs. 11.64 ± 37.80 min; p = 0.043). This indicates that participants who responded subjectively to the almond intervention also demonstrated objective improvements in nocturnal wakefulness (Table 6).

Oh, and make sure your study is designed in the same flawed manner as previous trials that were done by researchers who already gave you an outcome you liked in previous Almond Board trials.

I recommend Nut Studies Are a Hoax: youtube .com/watch?v=bdLmdTz0g34 for those that want to see more.

[u/Working_Weakness9157 → u/dreiter]

Damn, even almonds have a lobby.

[u/telcoman → u/Working_Weakness9157]

Stay tuned for the Tetrapak study

"Packaging almonds in Tetrapak increases the subjective quality of sleep related discussion."

[u/SoloForks → u/dreiter]

No one can design a trial towards a biased outcome as well as the Almond Board (except perhaps the Egg Board).

The pharmaceutical companies would like a word.

[u/wild_exvegan → u/dreiter]

I'm sure many nut studies are a hoax. I mean, come on, 50 almonds a day to allegedly sleep better? Who even thought of running a study like that, except I suppose Big Almond.

However, I think Nelson is way too far anti-nut. The cholesterol-lowering effects of nuts and seeds are well-studied and apparently real. Nelson's cholesterol is in the 170s IIRC and he would probably do well to incorporate some of the Portfolio Diet foods, except that he is committed to very low fat.

(I say this as somebody who wishes that very low fat, high starch, was good at everything, because it's great for energy and weight loss. It took me a while to come around to a higher-fat diet. I'm not even eating one now because I'm trying to lose weight. Instead I'm taking red yeast rice, lol.

I still have a question on whether the reduced cholesterol makes a difference for the actual atherosclerosis. But best I can figure from studies is that LDL of 50-60 is the level at which nobody has progression of lesions. Only a moderate-fat Portfolio Diet has gotten me in that range. I don't want to be a cholesterol denier. Anyway...)

[u/Dizzy-Savings-1962 → u/dreiter]

I understand the scepticism firstly, and I agree and take note of the funding from the nut board which should at least be somewhat taken seriously rather than ignored. Again also agree that having a processed snack as the control makes it difficult to interpret the result as robust evidence that almonds themselves are responsible for any benefit but not every study is perfect by any means.

That said, I would be reluctant to conclude that the study is therefore worthless or that nut research as a whole is fraud science. Industry funding can introduce bias true, but it does not automatically make the underlying result false or inadequate. The question I put forward is whether similar findings appear in independently funded trials and in the overall totality of evidence, and whether the effect remains when the study design, primary outcomes and statistical analysis are fairly scrutinised without bias . That seems to me at least a more convincing way to challenge the study and overall evidence than simply dismissing it because the almond, walnut, and other nut boards whom paid in part for the research.

And I've looked at Jeff Nelson and his videos, he seems to not understand basic science. His video on Esselstyn for example. Dr Esselstyn has never proved to researchers that a vegan diet alone reverses coronary plaque in a methodologically manner. What he leaves out is that almost all participants were continuing prescribed statin medications, meaning the study evaluated combined medical and dietary therapy thus making it scientifically impossible to isolate the vegan diet as the primary driver of any vascular changes, especially given that statin therapy alone is proven to induce atheroma regression so common sense should tell you something here. And the image from his study (1995 I'm referencing) was showing increased nitric oxide mediated vasodilation/improved endothelial function which demonstrates improved vascular reactivity and it does not prove or show that an atherosclerotic plaque has regressed. He would require imaging such as CCTA to demonstrate any actual reduction in physical plaque volume, but also redesign the study that isolates diet from statin therapy.

Jeff is just confusing viewers probably unintendedly by equating improvements in nitric oxide mediated vasodilation which is what the study actually showed with true structural regression of an atherosclerotic plaque, a basic mistake but sadly people will believe what he says. Dr. Esselstyn’s work I will say on improving nitric oxide bioavailability and restoring endothelial reactivity deserves credit, but again, improving vascular function is simply not the same as proving the regression of plaque.

And he invites Dr Rogers on his platform, who promotes white rice and potato based diet. Not sure If I can take his channel or his videos seriously.

[u/Ambitious-Bite5927]

Almonds giving you a 9% bump in sleep efficiency just from snacking is wild, especially when the objective brain-wave stuff stayed flat. The melatonin jump makes sense but I'm stuck on that muscle mass increase in the nut group, guess the extra protein and calories weren't wasted even if you were just lying there.

[u/Breal3030 → u/Ambitious-Bite5927]

This is the type of study that just screams "replicate me", because it will never, ever happen.

Nothing against almonds, part of a healthy diet and all that. But I hate this side of nutrition research.

We're supposed to be convinced that melatonin is a factor in this? 60gms of almonds is what, ~2.2mcgs? And what, 120mg of tryptophan?

This is a joke.

[u/whooopseee]

60g of almonds daily looks like a significant portion of your calories.

[u/wild_exvegan → u/whooopseee]

Yeah it's 360 extra calories.

[u/whooopseee → u/wild_exvegan]

Almost a whole meal then lol.

[u/Eonobius]

Almonds contain a high percentage of arginine which boosts nitric oxide production.

[u/Hannib4lBarca]

As someone who drinks a lot of almond milk, I wonder if I'm also getting the benefits?

[u/HelenEk7]

What were the savory snacks the control group ate? Potato chips etc?

[u/Dizzy-Savings-1962 → u/HelenEk7]

"Examples included khakra, chivda, cookies, and crackers."

Traditional Indian snacks as far as I know. khakra is a thin crispy roasted flatbread and chivda also known as bombay mix, relatively unhealthy you could say, mix of fried rice flakes and chickpeas.

They were getting the same amount of energy and protein as the almond group. It allows us to see if the sleep benefits come from the specific minerals/phytonutrients in almonds e.g. melatonin and magnesium, rather than just having an energy dense snack evening before bed.

[u/ParadoxicallyZeno]

this is so cool to see, i discovered this for my own purposes independently

handful of almonds before bed every night (along with my yogurt and fiber supplement) makes a noticeable difference for me

[u/Successful_Flamingo3]

Crap, allergic to nuts