1. Introduction
Avocados (
Persea americana) are botanically fruits and consist of a single large seed surrounded by a creamy, smooth-textured, edible fruit (known as pulp or mesocarp) covered by a thick, bumpy skin. The Hass avocado is the most consumed avocado variety in the United States and worldwide
[1]. Avocados have a unique physiology and nutritional composition when compared with other fruits. The fruits are picked when mature, but unripe, and the ripening process only begins after removal from the tree
[1]. Fresh avocados are eaten when ripe, and often consumed in spreads and dips such as guacamole, alone, as well as a topping for salads, soups, sandwiches, and burgers. The ripe fruit is rich in oleic acid, fiber, micronutrients (e.g., folate, vitamin K, copper, pantothenic acid), and various important phytochemicals, such as lutein, zeaxanthin, and phytosterols
[2].
The nutrients and bioactive molecules found in avocados contribute to several health benefits. Data from clinical trials and observational studies have linked avocado consumption with improvements in cardiovascular health, weight control, cognitive function, digestive physiology, and skin health
[3][4][5][6]. While these studies are reviewed in detail elsewhere, some key findings are summarized here briefly. Avocado intake improves lipid profiles in adults with dyslipidemia
[3] and supports weight management by reducing hunger and increasing meal satisfaction and satiety
[3]. Observational studies and clinical trials have found that avocado intake modestly improves cognitive function, especially in frontal cortex executive function
[5][7][8]. Avocado intake promotes changes in microbiota composition and fecal metabolites that correlate with a favorable metabolic phenotype in adults with overweight or obesity
[6]. Daily avocado consumption also enhances the elasticity and firmness of the facial skin in healthy women
[4]. Four key nutritional features likely mediate these beneficial effects: (1) a high unsaturated to saturated fatty acid ratio, (2) viscous, prebiotic fiber, (3) low energy density, and (4) highly bioavailable carotenoids
[3]. Additionally, preclinical studies have provided preliminary evidence that various parts of the avocado have anticancer, antimicrobial, and anti-inflammatory properties
[9].
2. Unique Nutritional Physiology and Ripening of Hass Avocados
Avocados differ substantially from other fruits both physiologically and in their propagation. Avocado varieties are classified into three groups or horticultural varieties, which are named for the geographic region in which they were domesticated: (1) Guatemalan (
P. americana var.
guatemalensis, L.O. Williams), (2) Mexican (
P. americana var.
drymifolia), and (3) West Indian (
P. americana var.
americana)
[10]. Each group has unique characteristics, including differences in leaf chemistry, peel texture and color, development period, fruit size, fruit oil content, cold hardiness, and salinity tolerance. Most of the varieties of interest for international trade are hybrids, which have been selected for fruit quality and disease and pest resistance
[1]. The Hass avocado is considered a Guatemalan/Mexican hybrid because it has the thick, rough skin of the Guatemalan variety, but the high oil content of the Mexican variety
[11]. The Hass avocado is commercially available in supermarkets throughout the United States and is responsible for 95% of the total commercialized volume
[1].
The ripening physiology of avocados is complex. Avocado trees have a long flowering period, lasting up to 3 months. However, the percentage of flowers that become mature fruit is extremely low (<0.1%)
[10]. Fruit maturation, which is the process of growth on the tree, requires 5 to 15 months after pollination
[12]. Fruit can remain on the tree for more than 12 months, far beyond the time needed to reach physiological maturity, but it does not ripen on the tree
[13]. Thus, at harvest, fruits of a broad range of physiological ages and maturity can be obtained from the same tree
[13]. The avocado is a climacteric fruit that only starts ripening after the fruit has been picked from the tree
[13].
The avocado is unique among fruits because it accumulates oil during growth and development, while most other fruits prioritize sugars. Oil accumulation begins in the mesocarp a few weeks after the flower forms a fruit, and it continues during growth and development, stopping when the fruit is harvested
[10]. Oil is stored as triacylglycerols, with the primary fatty acid being oleic acid. However, the oil’s fatty acid profile varies with geographical and environmental conditions
[10]. Based on dry weight, the mesocarp comprises approximately 60–70% oil and 10% carbohydrates
[10].
Another unique characteristic of the avocado is that it contains large amounts of seven-carbon (C7) sugars instead of six-carbon (C6) sugars as the predominant transport and storage sugars in its leaves and fruit
[10]. The sugars increase during the early stages of growth and development accompanying rapid fruit growth, and then decline as the metabolism shifts to oil accumulation
[10]. C7 sugars (mannoheptulose and perseitol) inhibit the ripening process, and they may also enhance fruit quality under commercial transport and storage conditions due to their antioxidant properties
[10][13].
3. Nutritional Composition of Ripe Hass Avocado Pulp
If the dry matter percentage was not reported in a study, a dry matter estimate (i.e., 27.7%) calculated from the average moisture reported on United States Department of Agriculture (USDA) FoodData Central was used to project the fresh matter weight of analytes or nutrients
[14]. The sample size for pooled means was determined by the number of individual analyses completed per publication or report. Pooled samples or technical replicates were considered
n = 1. The sample size was assumed to be one if not noted in the publication.
The USDA FoodData Central is an integrated data system that provides expanded nutrient profile data that defines Hass avocados as a standard reference legacy food: “Avocados, raw, California,”; their nutrient composition data are integrated in the tables below
[14]. The U.S. Nutrition Labeling and Education Act (NLEA) defines one serving of Hass avocado as 50 g (1/3 of a medium avocado), which provides 80 kilocalories, 8 g of total fat (5 g monounsaturated fatty acids), 3 g of fiber, and is a good source (≥10% dietary value (DV)) of vitamin K, folate, pantothenic acid, and copper
[14].
Analytical testing of avocado pulp was also conducted with Hass avocados available for distribution in the U.S. food supply, originating from various countries and across the growing seasons. Specifically, the analysis included fresh Hass avocado sampling from May 2021, June 2021, October 2021, and December 2021. Whole fresh avocados were randomly selected and directly shipped from regional avocado packing houses to a commercial food assurance lab for ripening and analytical testing. Additionally, whole fresh avocados sampled from September 2021 were randomly selected and shipped to an independent, third-party academic lab for ripening and analytical testing.
3.1. Energy and Water
The USDA reports a calculated energy content of 167 kcal/100 g avocado
[14]. The pooled data from existing literature, government nutrient databases, and commercial analyses yielded a mean total energy content of 194 kcal/100 g fresh avocado pulp (median: 184 kcal/100 g; range: 138–256 kcal/100 g; n = 11)
[15][16][17][18][19][20]. This corresponds to an energy density of 1.38–2.56 kcal/g. National Health and Nutrition Survey (NHANES) data shows the mean dietary energy density of the U.S. diet is 1.9 kcal/g
[21]. Additionally, Hass avocados contain 61–77% water by mass. Pooled mean total water content was 72.7 g/100 g fresh avocado pulp (median = 70; range = 61–77; n = 26)
[16][17][18][19][20][22][23]. Similarly, the USDA reports water content of 72.3 g/100 g avocado (range: 64–84 g/100 g; n = 33)
[14].
3.2. Lipids
The lipid content of fresh Hass avocado pulp is shown in
Table 1. The monounsaturated oleic acid (18:1n-9) is the predominant fatty acid in fresh avocados, accounting for approximately 59% of total fat based on USDA data. Palmitic acid (16:0) is the predominant saturated fatty acid accounting for 14% of total fat, while linoleic acid (18:2n-6) is the predominant polyunsaturated fatty acid, accounting for 11% of total fat (
Table 1). During ripening at 20 °C, palmitic acid content decreases and polyunsaturated fatty acids increase, while monounsaturated fatty acids remain relatively unchanged
[24]. However, preharvest conditions may influence fatty acid profiles. Lower growing temperatures shift the oil profile towards more oleic acid and less palmitic acid
[25].
The ratio of unsaturated to saturated fatty acids in avocados is approximately 6:1. Compared with other commonly consumed fat sources in the U.S. food supply, avocados have a high proportion of unsaturated fatty acids, similar to olive oil. Numerous health authorities, including the 2020–2025 Dietary Guidelines for Americans, American Heart Association, and the World Health Organization, recommend consuming foods rich in monounsaturated and polyunsaturated fatty acids instead of foods high in saturated and trans-fatty acids to reduce the risk of cardiovascular disease (CVD)
[26][27][28]. Observational study data suggest that replacing 5% of the energy intake from saturated fatty acids with monounsaturated fatty acids is associated with a 15% lower risk of developing coronary heart disease
[29]. The recommended energy displacement could be achieved with one avocado a day. Data from the same cohorts suggest eating one or more avocados weekly was associated with a 16% and 21% reduced risk of developing CVD and coronary heart disease, respectively
[30]. Research from clinical trials indicates that consuming at least one avocado per day over 4 to 5 weeks improves blood lipid profiles compared to control diets in healthy subjects with dyslipidemia and overweight or obesity
[3]. Replacing saturated fatty acids with unsaturated fatty acids is also associated with a significant reduction in total mortality
[31].
Table 1. Lipids in fresh Hass avocado pulp.
|
USDA Food Data Central |
Literature, Other Government Databases and Commercial Analyses |
g/100 g |
Mean |
Min, Max |
n |
Pooled Mean |
Min, Max |
n |
Refs. |
Total Fat |
15.4 |
8.4, 23.2 |
31 |
17.77 |
12.9, 26.7 |
28 |
[15][16][17][18][19][20][22][23] |
Saturated fatty acids |
2.13 |
NA |
1 |
3.18 |
0.85, 6.3 |
18 |
[15][16][17][18][19][20][23] |
16:0 Palmitic acid |
2.08 |
1.73, 2.54 |
8 |
1.27 |
0.54, 4.32 |
121 |
[16][17][23][32][33] |
18:0 Stearic acid |
0.05 |
0.007, 0.082 |
8 |
0.03 |
0, 1.98 |
202 |
[16][17][23][33] |
Monounsaturated fatty acids |
9.8 |
NA |
1 |
12.37 |
8.48, 19.51 |
18 |
[15][16][17][18][19][20][23] |
16:1n-7 Palmitoleic acid |
0.698 |
0.5, 0.881 |
8 |
0.53 |
0.11, 1.98 |
121 |
[16][17][23][32][33] |
17:1 |
0.01 |
0, 0.016 |
8 |
0 |
NA |
2 |
[17] |
18:1n-9 Oleic acid |
9.07 |
7.44, 10.9 |
8 |
4.07 |
1.5, 19.4 |
121 |
[16][17][23][32][33] |
18:1n-7 Cis-Vaccenic acid |
NA |
|
|
0.627 |
0.35, 0.84 |
109 |
[33] |
20:1n-9 Gondoic acid |
0.025 |
0.02, 0.033 |
8 |
0.02 |
0.02, 0.02 |
2 |
[17] |
Polyunsaturated fatty acids |
1.82 |
NA |
1 |
2.46 |
0.46, 4.55 |
18 |
[15][16][17][18][19][20][23] |
18:2n-6 Linoleic acid |
1.67 |
1.44, 1.97 |
8 |
0.93 |
0.29, 2.68 |
121 |
[16][17][23][32][33] |
18:2n-6 Linolelaidic acid |
NA |
|
|
1.60 |
1.54, 1.66 |
6 |
[23] |
18:3n-3 α-Linolenic acid |
0.11 |
0.096, 0.128 |
4 |
0.135 |
0, 0.33 |
13 |
[16][17][23][32] |
18:3n-6 γ-Linolenic acid |
0.015 |
0.015, 0.015 |
4 |
0.068 |
0, 0.1 |
110 |
[17][33] |
20:3n-6 |
0.016 |
0, 0.04 |
8 |
NA |
|
|
|
3.3. Carbohydrates
The carbohydrate content of fresh Hass avocado pulp is shown in
Table 2. Approximately 65–80% of the carbohydrates in avocado are dietary fiber and include a mix of insoluble and soluble fibers such as cellulose, hemicellulose, and pectin
[10]. The sugar content is low compared to other fruits due to their preferential oil accumulation
[10].
Compared with other commonly consumed fruits and vegetables in the U.S. food supply, avocados have a high fiber content. The current Dietary Guidelines for Americans identify fiber as a nutrient of concern because of low consumption among the U.S. population
[26]. While global guidelines generally recommend that adults consume 25–30 g of dietary fiber daily, North Americans consume an average of 17 g daily
[34]. A comprehensive body of literature shows that fiber has numerous health benefits, including improvement in laxation and regularity, reduced risk of CVD moderating effects on satiety and body weight, and beneficial effects on the microbiota and gut health
[34][35][36][37].
USDA FoodData Central reports 6.8 g/100 g of fiber in avocados, though this mean is over 1.5 times higher than the pooled data (3.87 g/100 g), and the amount of fiber reported is rather variable. Methodological differences in defatting or fiber analysis may contribute to this discrepancy. However, both USDA FoodData Central and the pooled data have high ranges, which suggests that sampling differences largely contribute to the high variability.
Table 2. Carbohydrates in fresh Hass avocado pulp.
|
USDA Food Data Central |
Literature, Other Government Databases and Commercial Analyses |
g/100 g |
Mean |
Min, Max |
n |
Pooled Mean |
Min, Max |
n |
Refs. |
Total carbohydrates |
8.64 |
NA |
1 |
5.82 |
3, 12.2 |
16 |
[16][17][18][19][20][23] |
Dietary fiber |
6.8 |
3.2, 12.7 |
21 |
3.87 |
2.2, 7.5 |
17 |
[16][17][18][19][20][23] |
Insoluble fiber |
NA |
|
|
2.63 |
2.56, 2.7 |
2 |
[15] |
Soluble fiber |
NA |
|
|
2.05 |
1.99, 2.11 |
2 |
[15] |
Total sugars |
0.3 |
0, 0.55 |
11 |
0.1 |
0, 0.8 |
8 |
[17][18][19][20] |
Sucrose |
0.06 |
0, 0.15 |
9 |
0.11 |
0.002, 0.43 |
25 |
[32][38][39] |
Glucose |
0.08 |
0.06, 0.24 |
9 |
0.03 |
0.002, 0.1 |
22 |
[38][39] |
Fructose |
0.08 |
0.07, 0.15 |
9 |
0.04 |
0.01, 0.1 |
22 |
[38][39] |
Galactose |
0.08 |
0, 0.3 |
8 |
NA |
|
|
|
Starch |
0.11 |
0.05, 0.17 |
4 |
NA |
|
|
|
3.4. Protein and Amino Acids
The protein content of fresh Hass avocado pulp is shown in Table 3. Although avocados contain various amino acids, they likely do not contribute a meaningful amount of protein toward daily needs.
Table 3. Protein and amino acids in fresh Hass avocado pulp.
|
USDA Food Data Central |
Literature, Other Government Databases and Commercial Analyses |
g/100 g |
Mean |
Min, Max |
n |
Pooled Mean |
Min, Max |
n |
Refs. |
Total protein |
1.96 |
1.53, 3 |
30 |
1.59 |
1.05, 2.4 |
45 |
[16][17][18][19][20][22][23][38] |
Amino acids |
|
|
|
|
|
|
|
Taurine |
NA |
|
|
0.02 |
NA |
1 |
|
Hydroxyproline |
NA |
|
|
0.04 |
NA |
1 |
|
Aspartic acid |
0.232 |
|
1 |
0.14 |
0.12, 0.15 |
2 |
[17] |
Threonine * |
0.072 |
|
1 |
0.07 |
0.06, 0.08 |
2 |
[17] |
Serine |
0.112 |
|
1 |
0.08 |
0.08, 0.08 |
2 |
[17] |
Glutamic acid |
0.28 |
|
1 |
0.15 |
0.14, 0.16 |
2 |
[17] |
Proline |
0.096 |
|
1 |
0.07 |
0.06, 0.08 |
2 |
[17] |
Lanthionine |
NA |
|
|
0.04 |
|
1 |
|
Glycine |
0.102 |
|
1 |
0.08 |
0.07,0.09 |
2 |
[17] |
Alanine |
0.11 |
|
1 |
0.09 |
0.07, 0.1 |
2 |
[17] |
Cysteine |
NA |
|
|
0.03 |
0.03, 0.04 |
2 |
[40] |
Cystine |
0.027 |
|
1 |
ND |
|
|
|
Valine * |
0.11 |
|
1 |
0.09 |
0.08, 0.1 |
2 |
[17] |
Methionine * |
0.04 |
|
1 |
0.03 |
0.02, 0.04 |
3 |
[17][40] |
Isoleucine * |
0.08 |
|
1 |
0.07 |
0.06, 0.08 |
2 |
[17] |
Leucine * |
0.14 |
|
1 |
0.11 |
0.1, 0.1 |
2 |
[17] |
Tyrosine |
0.05 |
|
1 |
0.1 |
0.04, 0.15 |
2 |
[17] |
Phenylalanine * |
0.1 |
|
1 |
0.07 |
0.06, 0.07 |
2 |
[17] |
Hydroxylysine |
NA |
|
|
0.03 |
|
1 |
|
Lysine * |
0.13 |
|
1 |
0.09 |
0.08, 0.1 |
2 |
[17] |
Histidine * |
0.05 |
|
1 |
0.03 |
0.03, 0.04 |
2 |
[17] |
Arginine |
0.09 |
|
1 |
0.08 |
0.07, 0.09 |
2 |
[17] |
Tryptophan * |
0.03 |
|
1 |
0.02 |
0.02, 0.02 |
2 |
[17] |
3.5. Vitamins
One medium-sized Hass avocado provides 30% daily value (DV) vitamin K, 30% DV folate, and 45% DV pantothenic acid (
Table 4). Vitamin K is vital for blood clotting, healthy bones, and other essential bodily functions. In a prospective cohort study of 56,048 participants, moderate-to-high vitamin K intake (87–192 µg/d) was linked with reduced risk of all-cause mortality, CVD-related mortality, and cancer-related mortality
[41]. Per USDA FoodData Central, avocado contains 21 µg vitamin K/100 g, but values may range from 5–27 µg/100 g. Although avocado provides only one-quarter the amount of vitamin K as one cup of raw spinach (145 µg) or kale (113 µg), it also provides lipids that enhance the absorption of fat-soluble nutrients
[42].
Folate is essential for maintaining a healthy pregnancy, and the 2020–2025 Dietary Guidelines for Americans identify folate as a nutrient of concern for reproductive-aged and pregnant females due to inadequate intake
[26]. The recommended dietary allowance for pregnant women is 600 µg dietary folate equivalents. Pregnancy is not the only physiological condition that may require dietary folate. A meta-analysis of 12 studies involving 2570 participants found that blood folate levels were significantly lower in inflammatory bowel disease patients compared to control patients
[43]. An umbrella review of 133 meta-analyses also reported the benefits of folate on all-cause mortality, multiple cancer types, CVD, and neurological conditions
[44]. USDA FoodData Central reported 89 µg/100 g of avocado, consistent with the 90 µg/100 g pooled mean from the literature, commercial, and other government databases.
Pantothenic acid is a critical cofactor for energy production, specifically triacylglycerol synthesis and lipoprotein metabolism. USDA FoodData Central reports 1.46 mg/100 g pantothenic acid in avocado, almost double the amount reported in the literature, commercial, and other government databases (0.89 mg/100 g), making it one of the richest sources of pantothenic acid.
One medium-sized Hass avocado also provides 12% DV of vitamin C, 18% DV of vitamin E, 24% DV of riboflavin, and 18% DV of niacin and vitamin B6. The means from USDA FoodData Central and pooled means are relatively consistent for vitamin B6 (0.287 vs. 0.28 mg/100 g, respectively), riboflavin (0.143 vs. 0.139 mg/100 g, respectively), niacin (1.91 vs. 2.07 mg/100 g, respectively), and α-tocopherol (1.97 vs. 2.13 mg/100 g, respectively). The means for the pooled vitamin C data are 6.19 mg/100 g with a range between 1.9–13 mg/100 g, suggesting sample or method variability may contribute to the differences between these data and USDA FoodData Central (8.8 mg/100 g).
Table 4. Vitamins in fresh Hass avocado pulp.
|
USDA Food Data Central |
Literature, Other Government Databases and Commercial Analyses |
Per 100 g |
Mean |
Min, Max |
n |
Pooled Mean |
Min, Max |
n |
Refs. |
Vitamin C (mg) |
8.8 |
6.3, 13.9 |
16 |
6.19 |
1.9, 13 |
15 |
[15][16][17][18][19][20][39] |
Thiamin (mg) |
0.075 |
0.052, 0.1 |
12 |
0.069 |
0.03, 0.119 |
10 |
[16][17][18][19][20] |
Riboflavin (mg) |
0.143 |
0.119, 0.18 |
12 |
0.139 |
0.12, 0.183 |
10 |
[16][17][18][19][20] |
Niacin (mg) |
1.91 |
1.46, 2.51 |
12 |
2.07 |
1.59, 2.6 |
10 |
[16][17][18][19][20] |
Pantothenic acid (mg) |
1.46 |
0.93, 2.71 |
12 |
0.89 |
0.65, 1.2 |
6 |
[16][17][18][19][20] |
Pyroxidine (mg) |
0.287 |
0.196, 0.452 |
11 |
0.28 |
0.1, 0.69 |
10 |
[16][17][18][19][20] |
Folate (µg) |
89 |
71, 155 |
20 |
90 |
61,120 |
10 |
[16][17][18][19][20] |
Biotin (µg) |
NA |
|
|
2.73 |
0, 5.6 |
6 |
[16][17][18][19][20] |
Vitamin A * (µg) |
7 |
NA |
NA |
10.5 |
6, 16 |
4 |
[17][18][19][20] |
α-tocopherol (mg) |
1.97 |
0.66, 3.28 |
22 |
2.13 |
0.94, 3.28 |
20 |
[16][17][39][45] |
β-tocopherol (mg) |
0.04 |
0.02, 0.06 |
9 |
0.01 |
0, 0.05 |
5 |
[17] |
γ-tocopherol (mg) |
0.32 |
0.09, 0.75 |
18 |
0.25 |
0, 0.75 |
14 |
[17][45] |
δ-tocohpherol (mg) |
0.02 |
0.01, 0.03 |
9 |
0.03 |
0,0.13 |
9 |
[17][39] |
Vitamin K (µg) |
21 |
15.7, 27 |
8 |
16.55 |
5, 25 |
6 |
[18][19][20] |
Other |
|
|
|
|
|
|
|
Choline (mg) |
14.2 |
NA |
NA |
19.5 |
19.3, 19.6 |
2 |
[16] |
3.6. Minerals
The mineral content of fresh Hass avocado pulp is shown in
Table 5. One medium-sized Hass avocado (150 g) provides 30% DV copper and 18% DV potassium. One avocado provides nearly 100% of the daily needs of copper for infants (0.2–0.22 mg). Copper is a cofactor for energy production pathways, iron metabolism, synthesis of connective tissues, lipid metabolism, and activation of neuropeptides
[46]. According to national survey data, about 30% of the general U.S. population does not meet recommended copper intake levels, which has been hypothesized to contribute, in part, to dyslipidemia
[46].
Potassium is critical in managing blood pressure
[47]. Dietary potassium intake of at least 2900 mg/d is associated with a reduced incidence of type 2 diabetes
[48], and intake >4000 mg/d is associated with a reduced risk of developing kidney stones
[49][50]. The 2020–2025 Dietary Guidelines for Americans identifies potassium as a nutrient of concern because of low intakes across the U.S. population
[26].
This entry is adapted from the peer-reviewed paper 10.3390/foods12132516