Introduction
Sarcopenia, characterized by the age-related decline in skeletal muscle mass and strength, is a growing health concern, particularly affecting the aging population. Typically starting around the age of 50, sarcopenia’s prevalence significantly increases with age, ranging from 5-13% in individuals aged 60-70 to a staggering 11-50% in those over 80 [1, 2]. This muscle loss leads to physical disability, reduced quality of life, and increased morbidity and mortality.
Fortunately, interventions exist to mitigate and prevent sarcopenia. Among the most effective strategies are physical exercise, especially resistance training, and dietary adjustments, often involving targeted nutritional supplements. For many older adults, especially those with limited mobility, nutritional intervention stands out as the most practical and crucial therapeutic approach [3]. Within the realm of nutrition, high biological value proteins and the amino acid leucine have garnered significant attention for their profound impact on skeletal muscle health [4]. Consuming protein-rich meals, particularly those abundant in leucine, is known to stimulate muscle protein synthesis, a key process in maintaining and building muscle mass [5]. However, aging often brings about a reduced muscle response to the anabolic effects of diet, a phenomenon known as anabolic resistance. This means older adults may require higher leucine intake to achieve the same muscle-building benefits as younger individuals [6, 7]. International guidelines now recommend a leucine intake of 3 grams per meal, alongside 25-30 grams of protein, across three main meals to effectively combat age-related lean mass loss [8].
One significant challenge in implementing these dietary recommendations is the lack of readily available information on leucine content in common foods. Food composition databases often omit leucine values, making it difficult for individuals and healthcare professionals to design diets that meet the recommended leucine intake.
This article aims to address this gap by providing a comprehensive guide to Leucine Rich Foods. By evaluating existing literature and food composition databases, we present detailed tables of leucine content in various food sources. This resource serves as a practical tool for individuals seeking to optimize their leucine intake and support muscle health, especially as they age. Understanding which leucine rich foods to incorporate into your diet is a vital step in combating sarcopenia and maintaining strength and vitality throughout life.
The Vital Role of Leucine in Preserving Muscle Mass
Research consistently highlights leucine’s pivotal role in counteracting muscle loss. Metabolic studies indicate that older adults (aged 65 and over) require approximately 20% more protein per meal compared to younger adults to maximize muscle protein synthesis. Leucine supplementation has emerged as a particularly effective strategy to meet these increased needs [3, 10].
L-leucine, an essential branched-chain amino acid (BCAA), along with L-valine and L-isoleucine, plays a crucial regulatory function in muscle metabolism. This regulation is largely mediated by mTOR (mammalian Target Of Rapamycin), a serine-threonine protein kinase that acts as a central regulator of cell growth and metabolism [3, 11]. mTOR and its associated signaling pathways are sensitive to energy levels and nutrient availability, particularly amino acids like leucine. When cellular ATP levels are high, indicating sufficient energy, mTOR is activated, promoting protein synthesis. Conversely, when ATP levels are low, mTOR is inhibited, conserving energy [12].
Unlike most other amino acids primarily metabolized in the liver, BCAAs are predominantly metabolized in skeletal muscle. Skeletal muscle houses the most active branched-chain amino acid oxidation system, including the enzyme BCAT (branched-chain aminotransferase) [13]. Leucine stands out for its direct signaling action, activating the mTORC1 complex. This activation triggers protein synthesis by stimulating translation initiation (phosphorylation of the translation initiation factor 4E-BP1) and suppressing protein degradation [6, 14]. Furthermore, leucine supplementation has shown promise in improving mitochondrial function within skeletal muscles, further supporting muscle health and energy production [3, 11].
Beyond its direct effects on muscle tissue, leucine also influences insulin and GLP-1 (Glucagon-Like Peptide 1) secretion. In pancreatic beta-cells, leucine acts as a secretagogue, enhancing glucose-induced insulin release. Moreover, it stimulates GLP-1 synthesis and secretion by L cells in the ileum and colon. GLP-1, in turn, enhances insulin sensitivity in muscle cells, improving glucose uptake and promoting anabolism, which is crucial for maintaining muscle mass [3, 11]. Therefore, incorporating leucine rich foods into your diet can have multifaceted benefits for muscle health, impacting protein synthesis, energy metabolism, and glucose regulation.
Image Alt Text: Lean chicken breast, a high-protein and leucine-rich food, shown cooked and sliced, ideal for muscle building diets.
The Link Between Leucine Blood Levels, Muscle Mass, and Performance
Plasma levels of branched-chain amino acids, including leucine, are notably influenced by dietary nutrient intake. Observations in both humans and animal models reveal elevated BCAA concentrations during fasting periods, while protein deprivation leads to a decrease. During fasting, increased muscle protein degradation is thought to be the primary mechanism, providing substrates for hepatic gluconeogenesis and BCAA oxidation in muscles. Conversely, protein deprivation reduces exogenous amino acid supply and muscle protein turnover, resulting in lower plasma BCAA levels [15].
In the post-meal period, a rapid increase in BCAA levels is observed, followed by uptake into muscle tissue. Studies have shown that even 12 hours after a high-protein meal, plasma BCAA concentrations remain elevated compared to a low-protein meal [16]. However, research findings on the direct correlation between fasting plasma BCAA levels and dietary intake are not always consistent. A Canadian study in 2019, involving 199 subjects aged 18–55, found no significant association between fasting plasma BCAA levels and total dietary intake. Interestingly, a weak correlation was observed between plasma BCAA concentrations and the consumption of animal-based proteins and red meat [17].
Studies focusing on elderly populations have revealed more pronounced associations between leucine levels and muscle health. In a study of 232 elderly Japanese women (average age 79.4 years), significantly lower blood leucine concentrations were found in women with dynapenia (reduced muscle function without muscle mass loss) and sarcopenia compared to healthy subjects. Generally, women with dynapenia and sarcopenia exhibited lower BCAA concentrations than those with normal muscle function and those with pre-sarcopenia (reduced muscle mass but normal muscle function) [18]. Similarly, a Norwegian cross-sectional study of 417 elderly individuals (aged 70 and older) found that plasma leucine and isoleucine concentrations were significantly lower in participants diagnosed with sarcopenia compared to healthy individuals, even after adjusting for gender. This difference was observed approximately 2 hours post-meal. Furthermore, plasma leucine levels positively correlated with skeletal muscle mass and grip strength. However, when data were adjusted for body weight, no significant difference in protein intake was found between the sarcopenia and healthy groups. These findings suggest a complex interplay between dietary leucine intake, plasma leucine levels, and muscle health in older adults [19].
Further supporting the link between leucine and muscle health, the Maastricht Sarcopenia Study (MaSS) in 227 community-dwelling seniors (average age 74 years) found that lower blood levels of essential amino acids, BCAAs, and leucine were associated with reduced skeletal muscle index (SMI), decreased grip strength, and poorer performance on the chair stand test. Sarcopenia was also more prevalent among individuals with lower levels of leucine, BCAAs, and essential amino acids [20]. Comparative studies across different age groups have also shown a trend of decreasing BCAA plasma levels with advancing age. A study comparing young adults, elderly individuals, and centenarians found progressively lower BCAA levels in both sexes with increasing age [21]. Similar findings were reported in a 1989 study showing significantly lower BCAA levels in healthy elderly men and institutionalized elderly men compared to healthy young men [22]. Another study involving 72 healthy subjects aged 23–92 years observed a decline in total amino acids, essential amino acids, non-essential amino acids, and BCAAs with increasing age. Men also exhibited higher concentrations of essential amino acids and BCAAs than women. The authors suggest that reduced serum amino acid concentrations in aging may be linked to decreased energy and protein intake, a common occurrence in older adults [23]. Conversely, a recent Korean study in adults aged 50–64 years found a significant positive association between dietary BCAA intake and skeletal muscle mass index (SMI), suggesting that adequate leucine intake from leucine rich foods is crucial for maintaining muscle mass even in middle age [24].
Image Alt Text: Sliced raw ham, a flavorful and leucine-dense meat product, displayed on a cutting board ready to eat, representing a high-leucine protein source.
Leucine Intervention Studies in Sarcopenic Elderly
Most clinical intervention studies investigating leucine’s effects on sarcopenia have focused on community-dwelling elderly individuals and utilized whey proteins as the primary leucine source, given their high leucine content (approximately 13 g leucine per 100 g protein). Fewer studies have examined supplementation with leucine alone [3].
A randomized controlled study in Spain involving 42 institutionalized elderly individuals (average age 78.9 years) demonstrated that administering 6 g/day of L-leucine for 13 weeks improved functional performance (gait speed) and respiratory muscle strength (maximum static expiratory pressure) compared to placebo. Leucine supplementation also prevented the decline in lean mass index. These findings suggest that L-leucine supplementation can provide beneficial effects for sarcopenia in elderly subjects, helping to maintain muscle mass and improve nutritional status [3]. Katsanos and colleagues observed that while both a mixture of essential amino acids (EAAs) containing 26% leucine (approximately 1.7 g) and an equal amount of EAAs with 41% leucine (approximately 2.8 g) increased muscle protein synthesis in young adults, only the higher leucine mixture was effective in elderly individuals [25]. A 2018 randomized controlled trial further emphasized the importance of leucine itself, rather than just total protein amount. Supplementation with 3 g of leucine twice daily, regardless of whether total protein intake was 10 g or 25 g twice daily, was primarily responsible for increased myofibrillar protein synthesis in healthy women aged 65–75 years [26]. The same research group previously showed that supplementing with 15 g of a protein drink containing 4.2 g of leucine twice daily for 6 days resulted in greater myofibrillar protein synthesis compared to a similar drink with only 1.3 g of leucine [7]. Even in healthy elderly men (aged 65–85 years), consuming 5 g of leucine at each of the three main meals for 3 days improved myofibrillar protein synthesis, regardless of whether their dietary protein intake was 0.8 g/kg or 1.2 g/kg of body weight per day [27].
A 2015 meta-analysis of 16 randomized controlled and cross-sectional studies involving a total of 999 elderly individuals found that leucine supplementation (2 to 7.8 g/day, from various sources) was associated with a significant increase in body weight and lean mass, particularly in sarcopenic subjects. However, no significant effect on muscle strength was observed [28]. Another meta-analysis in the same year, analyzing nine randomized clinical trials with 228 elderly individuals, also found that leucine administration (ranging from 2.6 to 17.6 g/day in acute studies and 2.8 to 16.1 g/day in longer-term studies) was associated with a significant increase in muscle protein synthesis rate, but not lean body mass or lower limb strength [14]. While the heterogeneity of these studies makes definitive conclusions challenging, the evidence suggests a plausible beneficial effect of leucine supplementation, and by extension, incorporating leucine rich foods, for individuals at risk of or suffering from sarcopenia [4].
Recommended Leucine Intake and Food Sources
For older adults, the recommended protein intake is 1.0–1.2 g/kg of body weight per day to maintain a positive protein balance and overcome the age-related anabolic resistance. However, studies indicate that a significant portion of the elderly population does not meet even the average daily protein intake recommendation for adults (0.8 g/kg body weight) [29, 30]. Specifically for leucine, the World Health Organization (WHO) recommends a daily BCAA intake of 39 mg/kg of body weight for leucine, 20 mg/kg for isoleucine, and 26 mg/kg for valine for healthy adults, with no specific adjustments for the elderly population [31]. Italian Ministry of Health guidelines suggest that total branched-chain amino acid intake should not exceed 5 g/day and recommend a leucine:isoleucine:valine ratio of 2:1:1 [32].
Based on literature analysis, the PROT-AGE Study Group proposed a higher anabolic threshold of protein intake for elderly individuals: 25–30 g of protein per meal, containing approximately 2.5–2.8 g of leucine, which is higher than recommendations for younger adults [29]. Achieving the recommended intake of 3 grams of leucine per meal, across three main meals, along with 25-30 grams of protein, is a crucial goal for preventing and reversing lean mass loss in older adults [29]. To facilitate this, it’s essential to identify and incorporate leucine rich foods into the diet.
Leucine is a ubiquitous amino acid, present in all proteins, but more concentrated in animal-based proteins. It’s practically impossible to isolate leucine intake entirely from total protein intake through diet [4]. Therefore, focusing on consuming a variety of leucine rich foods is the most practical dietary strategy.
Conclusion: Practical Guidance with Leucine Rich Food Tables
To address the challenge of limited leucine information in food databases, we have compiled comprehensive tables of leucine rich foods. Table 1, presented below, is the first of its kind in the literature, consolidating data from leading Italian food databases: the Banca dati di composizione degli alimenti- istituto europeo di oncologia (BDA-IEO) [33] and the Consiglio per la ricerca in agricoltura e l’analisi dell’economia agraria (CREA) [34]. This extensive table provides a wide selection of foods, making it easier to identify and incorporate leucine rich foods into your diet to meet recommended intake levels.
Table 2 offers practical dietary guidance by providing sample meal plans for breakfast, lunch, and dinner, each designed to deliver approximately 3 grams of leucine and 25 grams of protein. These meal plans offer concrete examples of how to integrate leucine rich foods into daily meals, making it simpler to follow leucine intake recommendations for muscle health. By utilizing these resources, individuals can make informed dietary choices to support muscle mass maintenance and combat sarcopenia through the strategic consumption of leucine rich foods.
Table 1. Leucine, Protein, and Energy Content per 100g of Food (Descending Order of Leucine)
| Food | Leucine (g/100 g) | Total protein (g/100 g) | Energy (kcal/100 g) |
|---|---|---|---|
| Meat | |||
| Bresaola | 2.651 | 32.0 | 152 |
| Speck | 2.326 | 28.3 | 303 |
| Raw ham | 2.211 | 26.6 | 284 |
| Guinea fowl’s breast, without skin | 2.180 | 25.8 | 121 |
| Turkey’s breast, without skin | 2.002 | 24.0 | 107 |
| Rabbit, low-fat meat | 1.987 | 23.7 | 102 |
| Chicken’s breast, without skin | 1.955 | 23.3 | 100 |
| Deer, without visible fat | 1.953 | 21.0 | 91 |
| Adult bovine’s rump | 1.894 | 22.0 | 111 |
| Soaked cod | 1.886 | 21.6 | 95 |
| Tuna fish | 1.871 | 21.5 | 159 |
| Guinea fowl’s thigh, without skin | 1.829 | 24.0 | 127 |
| Chicken’s wings, without skin | 1.717 | 20.3 | 193 |
| Baked ham | 1.695 | 19.8 | 215 |
| Sardines | 1.643 | 20.8 | 129 |
| Mackerel | 1.636 | 17.0 | 170 |
| Pork’s shoulder | 1.550 | 19.0 | 156 |
| Farmed sea bream, filets | 1.557 | 19.7 | 159 |
| Lamb | 1.532 | 20.0 | 159 |
| Gorgonzola | 1.530 | 19.1 | 324 |
| Melted chicken, without skin | 1.526 | 18.5 | 107 |
| Horse, fat and muscle tissue | 1.519 | 19.8 | 145 |
| Salmon | 1.496 | 18.4 | 185 |
| Cod | 1.484 | 17.0 | 71 |
| Robiol | 1.467 | 20.0 | 338 |
| Arachid butter | 1.465 | 22.6 | 623 |
| Sweet almonds, dried | 1.450 | 22.0 | 542 |
| Pistachios | 1.442 | 20.6 | 570 |
| Turkey’s thigh, without skin | 1.438 | 18.0 | 113 |
| Peas, dried | 1.406 | 21.7 | 306 |
| Mozzarella cheese | 1.400 | 18.7 | 253 |
| Millet | 1.389 | 11.8 | 343 |
| Sword fish | 1.373 | 16.9 | 109 |
| Herring | 1.341 | 16.5 | 216 |
| Sole | 1.336 | 16.9 | 86 |
| Anchovy | 1.331 | 16.8 | 96 |
| Dog fish | 1.300 | 16.0 | 80 |
| Cashew nuts | 1.280 | 15.0 | 604 |
| Persic fish | 1.252 | 15.4 | 75 |
| Crescenza | 1.250 | 16.1 | 281 |
| Pork’s sausage | 1.241 | 15.4 | 304 |
| Unsweetened cocoa powder | 1.238 | 20.4 | 355 |
| Surimi | 1.204 | 15.2 | 95 |
| Frozen shrimps | 1.179 | 13.6 | 63 |
| Corn | 1.168 | 9.2 | 357 |
| Spelled perlat, raw | 1.075 | 14.6 | 353 |
| Chicken egg | 1.041 | 12.4 | 128 |
| Semolina pasta | 1.033 | 13.5 | 341 |
| Bovine, calf, 4 months, low-fat meat | 1.029 | 20.7 | 92 |
| Corn flour | 1.028 | 8.7 | 341 |
| Trout | 1.028 | 14.7 | 86 |
| Nuts, dried | 1.011 | 14.3 | 702 |
| Cow ricotta | 0.997 | 8.8 | 146 |
| Cuttlefish | 0.985 | 14.0 | 72 |
| Milk flakes | 0.978 | 9.7 | 115 |
| Hazelnuts, dried | 0.930 | 13.8 | 625 |
| Spreadable cheese | 0.933 | 8.6 | 313 |
| Oat flour | 0.920 | 12.6 | 378 |
| Squid | 0.886 | 12.6 | 68 |
| Cod steaks | 0.862 | 11.0 | 191 |
| Chicken egg white | 0.862 | 10.7 | 43 |
| Dried fruit | 0.848 | 12.9 | 660 |
| Buckwheat | 0.837 | 12.4 | 329 |
| Rusks | 0.831 | 11.3 | 387 |
| Mussel | 0.824 | 11.7 | 84 |
| Octopus | 0.746 | 10.6 | 57 |
| Clam | 0.718 | 10.2 | 72 |
| Greek yogurt, low-fat | 0.707 | 9.0 | 51 |
| Bread | 0.691 | 9.0 | 275 |
| Cannellin beans dried, cooked, boiled | 0.682 | 8.0 | 107 |
| Polished rice | 0.590 | 6.7 | 334 |
| Borlotti beans dried, boiled | 0.563 | 6.9 | 106 |
| Chick peas dried, boiled | 0.549 | 7.0 | 132 |
| Lentils, dried boiled | 0.527 | 6.9 | 109 |
| Cannellin beans, canned, drained | 0.513 | 6.0 | 86 |
| Greek yogurt | 0.505 | 6.4 | 115 |
| Borlotti beans, boiled | 0.493 | 5.7 | 78 |
| Beans | 0.488 | 6.4 | 104 |
| Lentils, drained canned | 0.417 | 5.0 | 91 |
| Cow’s milk partially skimmed | 0.377 | 3.5 | 46 |
| Spinaches | 0.323 | 3.4 | 31 |
| Avocado | 0.315 | 4.4 | 238 |
| Sweetened cocoa soluble powder | 0.273 | 4.5 | 349 |
| Yogurt partially skimmed | 0.268 | 3.4 | 43 |
| Forest asparagus | 0.210 | 4.6 | 35 |
| Porcini mushrooms | 0.207 | 3.9 | 27 |
| Cestnut | 0.207 | 3.5 | 189 |
| Artichokes | 0.196 | 2.7 | 22 |
| Coultivated mushrooms, pleurotes | 0.172 | 2.2 | 37 |
| Green beans | 0.147 | 2.1 | 18 |
| Zucchini/courgettes | 0.130 | 1.3 | 11 |
| Potatoes | 0.122 | 2.1 | 85 |
| Fresh lettuce | 0.115 | 1.8 | 19 |
| Green cabage | 0.113 | 2.1 | 19 |
| Chard | 0.093 | 1.3 | 17 |
| Butter | 0.086 | 0.8 | 758 |
| Eggplant | 0.070 | 1.1 | 15 |
| Kiwi | 0.068 | 1.2 | 44 |
| Banana | 0.056 | 1.2 | 76 |
| Bluebarry | 0.054 | 0.9 | 49 |
| Raspberry | 0.051 | 1.0 | 34 |
| Strawberry | 0.046 | 0.9 | 27 |
| Fig | 0.040 | 0.9 | 47 |
| Pepperoni | 0.039 | 0.9 | 25 |
| Fresh ripe tomatoes | 0.030 | 1.0 | 19 |
| Peach | 0.029 | 0.8 | 27 |
| Melon | 0.028 | 0.8 | 33 |
| Cherry | 0.023 | 0.8 | 38 |
| Black cherry | 0.023 | 0.8 | 41 |
| Apricot | 0.022 | 0.4 | 28 |
| Orange | 0.022 | 0.7 | 37 |
| Ananas | 0.022 | 0.5 | 40 |
| Pear | 0.016 | 0.3 | 35 |
| Grapes | 0.014 | 0.5 | 61 |
| Apple with peel | 0.012 | 0.2 | 44 |
Table 2. Weekly Meal Plan with Leucine Rich Foods
| Breakfast | Lunch | Dinner | All day |
|---|---|---|---|
| Monday | |||
| Meal/Recipe | Low-fat milk (300 g) and rusks (30 g) with peanut butter (30 g) and fresh fruit (kiwi 150 g) | Pasta (100 g) with swordfish (80 g) and mintSalad (50 g) with cherry tomatoes (200 g)Greek yogurt (125 g) with dried sweet almonds (10 g), bitter cocoa (5 g) and banana (125 g) | Baked zucchini omelet (two eggs, zucchini 100 g, courgette flowers 2/3, Grana Padano 10 g, olive oil 5 mL, salt, pepper, thyme to taste) Toasted bread (100 g) with spinaches (200 g) Peach (150 g) with bitter cocoa (5 g) |
| Nutritional composition | E: 507 kcal (2,122,3 kJ), P: 22 g, L: 1,9 g | E: 841 kcal (3,520,43 kJ), P: 42.7, L: 3,15 g | E: 681 kcal (2,850,67 kJ), P: 37,6, L: 3,12 g |
| Tuesday | |||
| Meal/Recipe | Bread (50 g) with bresaola (50 g) accompanied with whole Greek yogurt (150 g) and fruit (kiwi 100 g) | Fregola with lentils (Fregola 80 g, dry boiled lentils 100 g, ripe tomatoes about 100 g, Grana Padano 20 g, extra virgin olive oil 5 mL, vegetable broth to taste, salt to taste)Zucchini (200 g)Partially skimmed white yogurt (125 g) with honey (10 g) and dried nuts (20 g) | Beef with grilled vegetables (Beef filet 120 g, eggplant 100 g, zucchini 100 g, potatoes 350 g, olive oil 5 mL, vinegar to taste, salt, parsley, basil to taste) Rice crackers (2: 16 g) Strawberries (50 g), peach (50 g), banana (50 g) |
| Nutritional composition | E: 369,7 kcal (1,547,56 kJ), P: 31,3 g, L: 2,5 g | E: 773,6 kcal (3,238,29 kJ), P: 35,2 g, L: 2,744 g | E: 752,8 kcal (3,151,22 kJ), P: 34,4 g, L: 2,698 g |
| Wednesday | |||
| Meal/Recipe | Pancake (partially skimmed milk 200 g, oat flour 50 g, two egg whites: 60 g) with hazelnut cream (toasted hazelnuts 45 g, 1 tablespoon of Stevia or other sweetener, bitter cocoa powder 4 g, 1 mL seed oil) and banana (150 g) filling | Pasta with agretti and ricotta (100 g semolina pasta, 100 g cow’s milk ricotta, 200 g agretti, 5 g grated parmesan, 5 mL extra virgin olive oil, fresh chili pepper to taste, a clove of garlic)Partially skimmed white yogurt (125 g) with sour cherries (150 g) | Grilled tuna with orange scent (Tuna filet 100 g, extra virgin olive oil 5 mL, rosemary to taste, a clove of garlic, juice of one orange) Potatoes (350 g), radishes (200 g) and rice crackers (2: 16 g) |
| Nutritional composition | E: 758,1 kcal (3,173,41 kJ), P: 28,5 g, L: 2,28 g | E: 716,55 kcal (2,999,48 kJ), P: 30,35 g, L: 2,54 g | E: 638,42 kcal (2,672,43 kJ), P: 31,87 g, L: 2,41 g |
| Thursday | |||
| Meal/Recipe | French toast with avocado, pine nuts, eggs and grain flakes (one boiled egg 60 g, ½ avocado 100 g, bread 50 g, parmesan 30 g, pine nuts 15 g) | Risotto with shrimps, asparagus, lemon and thyme (Polished rice 100 g, shrimps 100 g, asparagus 100 g, shallot to taste, juice of ½ lemon, two sprigs of thyme, chives, salt, pepper to taste, vegetable broth to taste)Beets (200 g)Green apple sorbet with pistachio grain (one green apple about 200 g, sugar about 10 g, pistachios 30 g, water half a glass, lemon juice to taste) | Chicken strips with peppers (Chicken breast 130 g, yellow and red sweet peppers 300 g, onion 20 g, white wine half a glass to evaporate 70 mL, olive oil 10 mL, salt to taste) Bread (preferably wholemeal) (120 g) Strawberries (150 g) |
| Nutritional composition | E: 593,9 kcal (2,486,07 kJ), P: 31,3 g, L: 2,45 g | E: 854,5 kcal (3,576,94 kJ), P: 39,34 g, L: 2,621 g | E: 675 kcal (2,825,55 kJ), P: 44,8 g, L: 3,557 g |
| Friday | |||
| Meal/Recipe | Low-fat milk (150 g) and toast (bread, 50 g) with smoked salmon (60 g), cream of cheese (25 g) and avocado (50 g) | Spelled with peas, asparagus and saffron (100 g spelled, 30 g dried peas, 100 g asparagus, 30 g feta, saffron in pistils, 5 mL extra virgin olive oil, salt to taste)Eggplants (200 mL)Partially skimmed white yogurt (125 g) with chopped hazelnuts (10 g) and cornflakes (30 g) | Turkey scaloppine with kiwi (Turkey breast 110 g, one kiwi 80 g, olive oil 5 mL, valerian 80 g, flour to taste, lemon juice to taste, salt to taste) Bread (preferably wholemeal) (120 g) Boiled chestnuts (45 g) |
| Nutritional composition | E: 492,2 kcal (2,060,35 kJ), P: 29,34 g, L: 2,46 g | E: 783,45 kcal (3,279,52 kJ), P: 40,79 g, L: 3,133 g | E: 629,8 kcal (2,636,34 kJ), P: 41,4 g, L: 3,179 g |
| Saturday | |||
| Meal/Recipe | Mini-pancakes with oat flour (40 g oat flour, 150 g egg white, baking powder), honey (5 g) and raspberries (150 g) and low-fat milk (200 mL) with bitter cocoa (5 g) | Risotto with sausage and spinaches (100 g polished rice, 70 g pork sausage, 40 g fresh raw spinach, 20 g Parmesan cheese, 5 mL extra virgin olive oil, vegetable broth, white wine to taste, salt, pepper, nutmeg to taste)Artichokes (200 g)Apple (150 g) | Chickpeas balls with paprika (Dried boiled chickpeas 150 g, one small potato about 80 g, Grana Padano 20 g, olive oil 5 mL, breadcrumbs to taste, eggs 30 g (half egg), sweet paprika, salt, pepper to taste) Potatoes (270 g), toasted bread (20 g), lettuce (80 g) Peach (150 g) |
| Nutritional composition | E: 413,4 kcal (1,730,49 kJ), P: 31,66 g, L: 2,6 g | E: 797,2 kcal (3,337,08 kJ), P: 31,05 g, L: 2,562 g | E: 796,4 kcal (3,333,73 kJ), P: 35,28 g, L: 2,611 g |
| Sunday | |||
| Meal/Recipe | Cup with milk flakes (150 g) and bitter cocoa (10 g), oat (30 g), fresh fruit (banana 100 g, blueberries 100 g, and splashed nuts (30 g) | Polenta with gorgonzola and sautéed mushrooms (100 g corn flour, 50 g gorgonzola, 200 g mushrooms, 10 g parmesan, 5 mL extra virgin olive oil, one clove garlic, salt, pepper, parsley to taste)Green beans (200 g)Kiwi (80 g), banana (80 g), blueberries (20 g) | Sorrentina sole (Sole 180 g, tomato puree approximately 100 g, one clove garlic, pitted black olives 15 g, olive oil 5 mL, flour to taste, salt, pepper, oregano, basil to taste) Rice (30 g), potatoes (300 g), fennels (200 g) Orange (150 g) |
| Nutritional composition | E: 491 kcal (2,055,33 kJ), P: 28,5 g, L: 2,28 g | E: 804,4 kcal (3,367,22 kJ), P: 32,4 g, L: 2,823 g | E: 683,8 kcal (2,862,39 kJ), P: 43,3 g, L: 3,011 g |
CHO, carcohydrates; E, energy; F, fiber; L, leucine; Li, lipids; P, proteins; S, sugars.
Author Contributions
MR designed and wrote the paper. MNi, GaP, MF, LO, GG, and AT wrote and edited the paper. MNa, CG, ED, AR, GiP, and SP visualized the paper. All authors read and approved the final manuscript.
Conflict of Interest
AR and GiP were employed by Indena SpA. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
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