An almond is not a true nut. It is the seed inside the stone of a fruit called a drupe, the same kind of fruit as a peach, plum or cherry, and the tree belongs to the same genus, Prunus. Wild almonds are bitter and toxic because they make amygdalin, a compound that releases cyanide when the kernel is crushed. The sweet almonds sold as food trace back to a single gene change that switched that production off.
The calories on the label are not quite the calories you absorb. Almond cells have tough walls that keep part of the fat locked inside, so in a controlled-feeding trial of 18 adults, whole almonds gave 129 kcal per 28 g serving, against 168 to 170 kcal predicted by the standard factors. Almond butter, whose cell walls are broken, came close to the predicted value.
An ounce (28 g) of raw almonds has 164 kcal, 14.2 g of fat (8.94 g of it monounsaturated), 6 g of protein, 3.5 g of fiber and 7.27 mg of vitamin E, which is 48% of the daily value. Much of the human research below was paid for by the Almond Board of California, which California almond growers fund through an assessment, so each card says so when the paper does.
Health benefits of almonds
The top findings from 30 studies, strongest evidence first
What the stars mean
- Strong. Several randomized trials, pooled in a meta-analysis, point the same way, or regulators (FDA or EFSA) have approved the claim.
- Moderate. Good randomized trials support it, but there are fewer of them, or their results vary.
- Limited. Small, short or single trials, or mixed results. Promising, but it needs confirmation.
Population and lab studies get no stars: they show a link or a mechanism, not proof.
How we rate evidence →- ★★★Lower “bad” LDL cholesterolAlmonds lowered LDL by a small amount (0.132 mmol/L across 36 publications of trials) in adults without heart disease. Another pooled analysis of 27 studies found a drop of 5.65 mg/dL.
- ★★Almost no effect on body weightAcross 37 trials, almonds lowered body weight by only 0.45 kg. In a calorie-cut diet trial, almond and nut-free groups both lost 7.0 kg in 3 months.
- ★★Arteries widened better after 6 weeksIn adults with above-average heart disease risk, almonds as a snack raised flow-mediated dilation (how well arteries widen) by 4.1 percentage points more than muffins. LDL also fell by 0.25 mmol/L.
- ★★Slightly lower inflammation markersAcross 18 trials, almonds lowered CRP by 0.25 mg/L and IL-6 by 0.11 pg/mL, two markers of inflammation. The CRP drop only showed at doses under 60 g a day.
- ★★Slightly lower bottom blood pressure numberAcross 16 trials, the bottom number (diastolic) fell by 1.30 mm Hg. The top number did not clearly change (0.83 mm Hg, which could be chance).
All 30 studies, strongest evidence first
Across 36 publications of randomized trials, almonds lowered LDL cholesterol by 0.132 mmol/L in adults without heart disease
Meta-analysis of trials lasting at least 4 weeks (48 almond and control datasets, 2,485 people) in which the control diet had no nuts. Total cholesterol fell 0.160 mmol/L, non-HDL cholesterol 0.204 mmol/L and ApoB 4.552 mg/dL, while HDL did not change and triglycerides fell only by a borderline amount. The results held in the higher-quality studies. The Almond Board of California paid for the analysis and the authors work for a firm that consults for it; the Board had no role in the design, analysis or publication.
A pooled analysis of 27 studies found almonds lowered LDL cholesterol by 5.65 mg/dL
Meta-analysis of randomized trials in adults, with 1,154 people eating almonds and 904 controls. Triglycerides fell 6.68 mg/dL and total cholesterol 4.92 mg/dL, while HDL did not change significantly. The authors say more trials in people with abnormal blood fats are needed.
Across 61 trials of tree nuts, including almonds, each daily serving lowered LDL cholesterol by 4.8 mg/dL
Meta-analysis of 61 controlled trials (2,582 people) of walnuts, pistachios, almonds, hazelnuts and other tree nuts, so this is a result for nuts as a group, not almonds alone. Per 1-ounce serving (28.4 g) a day, total cholesterol fell 4.7 mg/dL and ApoB 3.7 mg/dL. Effects were stronger at 60 g or more a day and did not differ significantly by nut type.
A review of 15 trials found almonds lowered LDL cholesterol by 5.83 mg/dL and body weight by 1.39 kg
Meta-analysis of randomized trials lasting at least 3 weeks, with 534 people in all. Total cholesterol fell 10.69 mg/dL and ApoB 6.67 mg/dL, but HDL cholesterol also fell 1.26 mg/dL, and triglycerides and systolic blood pressure did not change. The authors note large differences between the trials, which limits firm conclusions. The Almond Board of California and the USDA supported the review, and the Board had no role in selecting or analyzing the studies.
Snacking on whole almonds for 6 weeks lowered LDL cholesterol by 0.25 mmol/L and improved artery widening
Randomized trial in adults aged 30 to 70 with above-average heart disease risk, comparing roasted almonds (51 people) with mini-muffin snacks (56), each providing 20% of daily energy. Flow-mediated dilation, a measure of how well arteries widen, rose 4.1 percentage points more on almonds. Liver fat, triglycerides, HDL, blood pressure and body composition did not differ. The Almond Board of California funded the trial and supplied the almonds.
In 37 randomized trials, almonds lowered body weight by only 0.45 kg and hunger scores slightly
Dose-response meta-analysis with 43 treatment arms. Waist circumference fell 0.66 cm, fat mass 0.66 kg and hunger scores 1.15 mm, while BMI and body fat percent did not change significantly. The benefit appeared at 50 g or more a day for at least 12 weeks and in people with a BMI under 30. The authors rate the certainty as very low for some outcomes and moderate for others.
Almonds in a calorie-cut diet did not change weight loss: both groups lost 7.0 kg in 3 months
Randomized trial in adults with overweight or obesity (68 on an almond-enriched diet, 72 on a nut-free diet with carbohydrate snacks), both cutting energy by 30%, followed by 6 months of weight maintenance. Glucose, blood pressure and LDL improved alike in both groups, while small LDL particles and very small triglyceride-rich particles fell more with almonds. The Almond Board of California supported the study.
Almonds lowered CRP by 0.25 mg/L and IL-6 by 0.11 pg/mL, two markers of inflammation, across 18 trials
Meta-analysis of randomized trials with 847 people. The CRP drop showed only at doses under 60 g a day and was not significant in unhealthy people or people with obesity. TNF-alpha, ICAM-1 and VCAM-1 did not change significantly. The authors say more trials are needed.
Across 16 trials, almonds lowered diastolic blood pressure by 1.30 mm Hg but not systolic pressure
Meta-analysis of randomized trials with 1,128 people. Systolic pressure fell 0.83 mm Hg, which could be chance (range −2.55 to 0.89), and results for it varied between trials. The authors point out that almonds are high in calories, so the amount should fit a healthy diet.
Pooling 24 trials, almonds did not significantly change fasting blood sugar, insulin or HbA1c
Meta-analysis of 24 studies (31 arms) that measured fasting blood sugar, insulin, insulin resistance (HOMA-IR) and HbA1c, a marker of long-term blood sugar. The authors found no convincing evidence of a clear benefit for glycemic control and call for more studies.
In 9 trials in people with type 2 diabetes, almonds lowered LDL cholesterol by 5.28 mg/dL and changed little else
Meta-analysis of randomized trials. The LDL drop was clearest above 50 g a day and with a starting LDL under 130 mg/dL. Total cholesterol, triglycerides, HDL, fasting blood sugar, insulin, HbA1c, weight, blood pressure and CRP did not change significantly. The authors ask for higher-quality studies.
Almonds in the diet gave 129 kcal per 28 g serving, not the 168 to 170 kcal predicted
Controlled-feeding crossover trial in 18 healthy adults who ate 0, 42 or 84 g of almonds a day for 18 days, with stool and urine collected for the last 9 days to measure the energy the body kept. The measured value was 4.6 kcal per gram, against the 6.0 to 6.1 predicted by the Atwater factors, which overestimated it by 32%. It applies to whole almonds in a mixed diet. The USDA and the Almond Board of California supported the study, and the Board had no role in its design, analysis or interpretation.
Whole natural almonds gave 4.42 kcal per gram, while almond butter gave 6.53, so the form changes the calories you absorb
Randomized crossover study in 18 healthy adults who ate 42 g of almonds a day in five forms: whole natural, whole roasted, chopped, almond butter and none. Roasted almonds gave 4.86 kcal per gram and chopped almonds 5.04, all below the Atwater prediction, while almond butter was close to it. Whole natural almonds broke into fewer, larger pieces, which the authors link to less fat released. The Almond Board of California supported the work.
Chewing almonds only 10 times raised the fat and energy lost in stool compared with 40 chews
Randomized crossover study in 13 healthy adults who chewed 55 g of almonds 10, 25 or 40 times, then ate 55 g a day under the same chewing rule for 4 days. Fecal energy loss was higher after 10 and 25 chews than after 40. After 40 chews, hunger was suppressed and fullness stayed higher longer than after 25. It was a very small study.
About 73 g of almonds a day for a month lowered LDL cholesterol by 9.4% in people with high cholesterol
Randomized crossover trial in 27 men and women with high cholesterol. Each ate three supplements of about 423 kcal a day for 1 month: full-dose almonds, half almonds with half muffins, or muffins. Half-dose almonds lowered LDL 4.4%, and the full dose also lowered lipoprotein(a) by 7.8% and oxidized LDL by 14.0%, while the muffin diet did not. Body weights differed by less than 300 g between diets.
Almonds supplying 20% of calories for 16 weeks lowered LDL cholesterol by 12.4 mg/dL and insulin in adults with prediabetes
Randomized trial in 65 adults with prediabetes on an American Diabetes Association diet, with or without about 2 oz of almonds a day. Insulin fell 1.78 µU/ml on almonds and rose 1.47 in the nut-free group, and insulin resistance also improved. LDL fell 0.4 mg/dL without almonds. BMI, blood pressure and the other risk factors did not change.
Adding 100 g of almonds a day to statin treatment lowered non-HDL cholesterol by 4.9% in 4 weeks
Randomized trial in 48 people already on a steady statin dose: 22 added almonds to a cholesterol-lowering diet and 26 followed the diet alone. Non-HDL cholesterol rose 3.5% without almonds. LDL and triglycerides improved but narrowly missed significance, and the almond group ate significantly more calories. The Almond Board of California was among the funders.
Two ounces of raw almonds a day for 16 weeks did not change HbA1c in adults with elevated values
Randomized trial in 81 adults with HbA1c above 5.7%, who added almonds (39 people) or energy-matched snacks (42). The almond group took in 253 kcal a day more, with no significant difference in body weight, blood chemistry, body composition or blood sugar response. Healthy Eating Index scores improved with almonds. The Almond Board of California funded the study.
Eating 50 g of almonds a day for 5 months lowered insulin sensitivity in people with prediabetes
Randomized crossover trial in 43 adults with overweight or obesity and prediabetes, with a clamp test as the measure. After the almond period, blood sugar after meals and fasting insulin were higher, and BMI and waist circumference had risen along with energy intake. The effect stayed after correcting for BMI, and the authors suggest almonds did not fully replace other foods. The Almond Board of California funded the study, and the authors report no conflict of interest.
Eating 56.7 g of almonds a day for 8 weeks lowered the 2-hour blood sugar response by 13% in college students
Randomized trial in 73 college students with no cardiometabolic disorders (38 on almonds, 35 on graham crackers). The insulin resistance index was 34% lower and the Matsuda index 82% higher on almonds, and HDL fell less (13.5% against 24.5%), despite similar weight gain. Both snacks lowered fasting glucose and LDL. The Almond Board of California funded the study and had no role in its design, analysis or write-up.
An almond snack lowered hunger over the morning compared with crackers or water, but not 24-hour calorie intake
Crossover trial in 42 young women tested in a lab. Almonds scored higher on a satiety measure than crackers and cut the pull of high-fat foods, but total energy intake over 24 hours did not differ between almonds, crackers and water. The Almond Board of California funded the work.
Eating almonds for 3 weeks raised gut bacteria such as Lachnospira, Roseburia and Dialister
Controlled-feeding crossover trial in 18 healthy adults who ate 42 g a day of whole, roasted, chopped or butter almonds, or none, each for 3 weeks. Chopped almonds raised Lachnospira, Roseburia and Oscillospira, whole almonds raised Dialister, and almond butter did not differ from control. The trial measured bacteria, not health. The Almond Board of California and the USDA gave partial support.
Eating 56 g of almonds a day for 8 weeks changed gut bacteria and raised their diversity in adults with raised blood sugar
Randomized trial in 69 overweight or obese adults, comparing almonds with an isocaloric high-carbohydrate biscuit snack. Ruminococcaceae bacteria rose, while stool short-chain fatty acids did not change and gut permeability was not lower. Stool pH and moisture fell. The authors say the benefit to the person is not known. The Almond Board of California funded the trial.
Almonds for 12 weeks lowered triglycerides and systolic blood pressure but did not change thinking or mood in older adults
Randomized trial in 128 overweight or obese adults aged 50 to 80, comparing an almond-enriched diet (63 people) with an isocaloric nut-free diet (65), each supplying 15% of energy. Working memory, the main outcome, did not change, and no other cardiometabolic marker differed. The Almond Board of California funded the research, and one author has consulted for an Australian tree-nut industry group.
Eating almonds for 24 weeks reduced facial wrinkle severity by 16% in postmenopausal women
Randomized trial in postmenopausal women with fair skin (Fitzpatrick types I or II) who took 20% of daily energy as almonds or a calorie-matched snack. Wrinkle severity was 15% lower than at the start at week 16, and pigment intensity 20% lower. Skin hydration and water loss did not differ from the control group. Only one narrow group was studied. The Almond Board of California funded it.
People who ate nuts 7 or more times a week had a 20% lower risk of dying than those who ate none
Two US cohorts, 76,464 women in the Nurses’ Health Study and 42,498 men in the Health Professionals Follow-up Study, with 16,200 women and 11,229 men dying during follow-up. The hazard ratio was 0.80, and deaths from cancer, heart disease and respiratory disease were also lower. It covers nuts as a group, not almonds alone. The National Institutes of Health and the International Tree Nut Council Nutrition Research and Education Foundation funded it.
Each extra 28 g of nuts a day went with a 22% lower risk of dying from any cause
Meta-analysis of 20 prospective studies. Per 28 g a day, the relative risk was 0.78 for all-cause death, 0.71 for coronary heart disease and 0.85 for total cancer, while stroke showed no clear link (0.93, range 0.83 to 1.05). Results varied between studies (I2 of 66% for all-cause death). It covers nuts as a group, from food questionnaires, and a link does not prove cause.
When almond tissue was chewed or crushed, only the first layer of cells released its fat
Lab and microscope work, plus stool samples from healthy volunteers. Cell walls were rich in non-starch polysaccharides, a type of fiber, and intact almond cells with fat still inside turned up in stool after an almond diet. The authors conclude that the cell walls hold back fat, which helps explain why some of it is not absorbed.
Intact almond cell walls limited fat digestion in lab digestion tests
Digestion model using raw and roasted almond cells and isolated oil bodies with stomach and gut enzymes. Intact cell walls hindered the fat-digesting enzyme lipase from reaching the fat inside, and fat breakdown products from leaving. It was not tested in people.
Almond skins raised bifidobacteria in a gut fermentation model, with a prebiotic index of 3.2 to 3.3
Lab model of digestion followed by fermentation with mixed stool bacteria. Natural and blanched skins both raised bifidobacteria and the Clostridium coccoides and Eubacterium rectale group, while fructo-oligosaccharides, a commercial prebiotic, scored 4.2. Only the skins were tested, not whole almonds, and no people took part.
Who should be careful with almonds
Most people can eat almonds freely. Take a little care if one of these applies:
- Tree nut allergy. Tree nuts are one of the nine major food allergens named by the FDA, and US labels must name the specific nut, such as almonds. If you have a tree nut allergy, avoid almonds unless your allergist says otherwise.
- Bitter almonds. Sweet almonds are the ones sold as food. EFSA found raw bitter almonds hold 500 to more than 1,000 mg of cyanide per kilogram, against about 25 mg in sweet almonds, and that 0.1 to 1.4 g of raw bitter almonds can reach the acute safe limit. Do not eat them raw.
- Calcium oxalate kidney stones. The US National Institute of Diabetes and Digestive and Kidney Diseases lists nuts among the foods people with these stones may want to avoid. Ask your clinician how much, if any, suits you.
How to choose, store and eat almonds
- Whole natural: the fewest calories absorbed, 4.42 kcal per gram, against 6.53 for almond butter. Chewing 10 times instead of 40 left more fat and energy in stool.
- Roasted or chopped: 4.86 and 5.04 kcal per gram, so more of their energy is absorbed than from whole natural almonds.
- Raw on the label: California almonds sold as raw have been pasteurized since September 1, 2007, a treatment that cuts Salmonella at least 10,000-fold. Untreated almonds are allowed only for makers who treat them or for shipment outside the US, Canada and Mexico, and must be marked unpasteurized.
Pick whole almonds without cracks or stale smell and keep them in an airtight container; they last around a year in the fridge and go rancid sooner when warm. Residues are no reason to skip them: in USDA tests of 177 almond samples in 2023, no sample went over a legal tolerance, and one had a single residue for which no tolerance is set.
Sources
- Food allergies. US Food and Drug Administration.
- EFSA Panel on Contaminants in the Food Chain (CONTAM). Evaluation of the health risks related to the presence of cyanogenic glycosides in foods other than raw apricot kernels. EFSA J. 2019.
- Eating, diet, and nutrition for kidney stones. National Institute of Diabetes and Digestive and Kidney Diseases.
- Gebauer SK, Novotny JA, Bornhorst GM, Baer DJ. Food processing and structure impact the metabolizable energy of almonds. Food Funct. 2016.
- Cassady BA, Hollis JH, Fulford AD, Considine RV, Mattes RD. Mastication of almonds: effects of lipid bioaccessibility, appetite, and hormone response. Am J Clin Nutr. 2009.
- Almonds grown in California; outgoing quality control requirements. Final rule, Federal Register 72(61):15021. USDA Agricultural Marketing Service. 2007.
- Pesticide Data Program annual summary, calendar year 2023. USDA Agricultural Marketing Service.
- Getting enough fibre: low FODMAP foods and IBS. Monash FODMAP blog.
- Almond. Wikipedia.
History of almonds
The almond began as a bitter, poisonous seed. Wild almonds make amygdalin, and almond domestication was enabled by picking trees with sweet kernels. A 2019 genome study traced the sweet trait to one change in a gene called bHLH2, a Leu to Phe swap that stops the plant from switching on two genes needed to make amygdalin.
Where almonds first grew is still debated. Some sources point to Central Asia, others to West Asia and the Levant, and the most recent ones name Iran and Anatolia, with Iran as the main center. The wild form grew in parts of the Levant, and people carried the crop along the Mediterranean shores into North Africa and southern Europe.
Almonds were among the first fruit trees people domesticated, partly because a tree can be grown from seed and still give good nuts, so no grafting was needed. Domesticated almonds show up in Early Bronze Age sites, 3000 to 2000 BCE, such as Numeira in Jordan, or possibly earlier. They were also found in Tutankhamun’s tomb, from about 1325 BCE, and were probably imported from the Levant.
The Swedish botanist Carl Linnaeus named the almond Amygdalus communis in 1753. Ibn al-‘Awwam’s 12th-century Book on Agriculture already has an article on growing almond trees in Spain. Much later the crop reached California, which now grows about 80% of the world’s almonds.
California’s almond trees need pollen from other varieties, so every February more than 1 million hives, nearly half of all beehives in the US, are trucked into the orchards. It is the largest managed pollination event in the world.
Raw almonds caused a food safety scare. A Salmonella Enteritidis outbreak in 2000 and 2001 caused 168 confirmed cases, 157 in Canada and 11 in the US, and a case-control study traced it to raw whole almonds; it was the first time almonds had been identified as the source of a foodborne outbreak. A second outbreak in Oregon in 2004 led to a recall of 5 million pounds that grew to about 15 million. In March 2007 the USDA published a rule that required California handlers to treat almonds for a 4-log reduction in Salmonella, 10,000-fold, with compliance mandatory from September 1, 2007.
Sources
- Sánchez-Pérez R, Pavan S, Mazzeo R, et al. Mutation of a bHLH transcription factor allowed almond domestication. Science. 2019.
- Almond. Wikipedia.
- Isaacs S, Aramini J, Ciebin B, et al. An international outbreak of salmonellosis associated with raw almonds contaminated with a rare phage type of Salmonella enteritidis. J Food Prot. 2005.
- Almonds grown in California; outgoing quality control requirements. Final rule, Federal Register 72(61):15021. USDA Agricultural Marketing Service. 2007.
Frequently asked questions about almonds
Are almonds good for you?
For most people, yes. An ounce (28 g) of raw almonds has 164 kcal, 3.5 g of fiber, 6 g of protein and 48% of the daily value of vitamin E. Across 36 publications of trials, almonds lowered LDL cholesterol by 0.132 mmol/L, a small effect, and effects on weight, blood sugar and blood pressure are small or absent. Large cohorts link nuts as a group to a 20% lower risk of dying, but that is a link, not proof.
How many almonds should you eat a day?
No study here sets an ideal number. Trials used 42 g a day for calorie absorption, about 73 g for cholesterol and 2 oz in diabetes-risk trials, and the FDA claim for nuts refers to 1.5 ounces a day. An ounce is 164 kcal, and people eating 2 oz a day took in 253 kcal more than the control group. If you have irritable bowel syndrome, Monash University lists 10 almonds (12 g) with skin as a low-FODMAP serving.
Do almonds lower cholesterol?
Yes, modestly. Pooled trials found LDL drops of 0.132 mmol/L across 36 publications and 5.65 mg/dL across 27 studies, and a 6-week trial found 0.25 mmol/L. HDL did not change in most analyses. In people already on a statin, adding 100 g of almonds lowered non-HDL cholesterol by 4.9%.
Can almonds make you gain weight?
They can if they add to what you already eat, though trials show little weight change. Across 37 trials body weight was only 0.45 kg lower, and in a calorie-cut diet almonds gave the same 7.0 kg loss as a nut-free diet. In 43 adults with prediabetes, 50 g a day for 5 months raised BMI. Part of the calories are never absorbed, 129 kcal against 168 to 170 predicted for a serving of whole almonds.
Are raw, roasted or soaked almonds better?
No trial here shows one is healthier. The form changes calorie absorption: 4.42 kcal per gram from whole natural almonds, 4.86 from roasted, 5.04 from chopped and 6.53 from almond butter. No study here tested soaking. Almonds sold as raw in the US have been pasteurized since 2007.
Are almonds poisonous?
Sweet almonds, the kind sold as food, are not. Bitter almonds are: EFSA found they hold 500 to more than 1,000 mg of cyanide per kilogram, against about 25 mg in sweet almonds, and that 0.1 to 1.4 g of raw bitter almonds can reach the acute safe limit. That is less than half a small kernel for a toddler and about one large kernel for an adult.
Are almonds good for people with diabetes?
They can fit, but trials show no clear blood sugar benefit. Across 24 trials, almonds did not significantly change fasting blood sugar, insulin or HbA1c, and in 81 adults with elevated HbA1c they did not change it over 16 weeks. In 43 adults with prediabetes, insulin sensitivity fell after 5 months of 50 g a day. Check portions and choices with your care team.
Are almonds nuts?
Botanically no, but for allergy labels yes. An almond is the seed of a drupe, like a peach stone. The FDA counts almonds as a tree nut, one of the nine major allergens, and US labels must name the nut.