A Review of the Health Benefits of Processed Lentils (Lens culinaris L.)

Lentil (Lens culinaris L.) is a versatile and nutrient‐dense food legume crop with demonstrated health benefits. As people are trying to minimize health‐related issues through healthy eating, lentils are gaining more popularity. Several processing methods, including heating, germination, fermentation, and extrusion, are frequently utilized to prepare this extensively consumed legume, transforming it into delicious and nutritious dishes while also optimizing its medicinal attributes. However, both in vitro and in vivo studies using the processed lentils effectively demonstrated their functional benefits including cardioprotective, antidiabetic, anti‐inflammatory, and anticarcinogenic activities. These facts make a strong case that consuming processed lentils can lower the likelihood of developing noncommunicable chronic illnesses like diabetes, cancer, heart disease, and so on. The conservation of bioactive substances including phenolic compounds and flavonoids is key to the processed lentils' beneficial health effects. These bioactive compounds have an impact on human physiology, neutralizing the excess free radicals or oxidants from damaging cell, which leads to improved health and well‐being. In this article, we reviewed and summarized the results from studies on processed lentils that have an impact on human health. By combining available studies, this review article provides an up‐to‐date and well‐informed viewpoint on improving health through dietary interventions, specifically looking at processed lentils and their potential to systematically lower disease risk and obtain health benefits.


| Introduction
Lentils (Lens culinaris L.), similar to other food legumes or pulses, are nutrient dense with reported positive health implications.Several recent studies have demonstrated that legumes, particularly lentils, may offer additional health advantages to fulfill a person's basic nutritional needs.The consumption of lentils has been linked to a decrease in the occurrence of several chronic diseases, such as cancer, diabetes, coronary heart disease, degenerative disorders, and aging (Ganesan and Xu 2017a;B. Zhang et al. 2018).Epidemiological investigations have also demonstrated a connection between eating lentils and a lower prevalence of the chronic illnesses including, cancer, heart disease, and diabetes (Faris, Mohammad, and Soliman 2020).The inclusion of phytochemicals such as polyphenols, saponins, and phytosterols in a diet high in pulses, such lentils, contributes significantly to the beneficial health effects (Mustafa et al. 2022).
Processing or cooking of lentils is necessary to make them palatable, enhance their digestibility, and inactivate or eliminate antinutrients (Kaale, Siddiq, and Hooper 2023).The raw lentils contain several antinutrients, for example, trypsin inhibitors, phytate, tannins, and flatulence-causing oligosaccharides.Therefore, only processed or fully cooked lentils are safe for human consumption, as consuming unprocessed/undercooked lentils would cause sickness resulting from significant digestive discomfort in animals, including humans (Dhull et al. 2023;Sparvoli, Bollini, and Cominelli 2015).Cooking of lentils is relatively quick and simple since longer cooking times are not required, as is the case with most of other pulses and dry beans (Kaale, Siddiq, and Hooper 2023).
Lentils possess multiple anti-inflammatory properties that have the potential for use in both dietary and therapeutic applications (Alexander et al. 2024).Diets possessing anti-inflammatory properties have the potential to minimize the inflammatory processes resulting from illnesses and bad eating habits.The healthy diets that include legume foods promote antiaging lifestyle (Stromsnes et al. 2021).The heightened importance of research on health-related topics in recent years is evident from a recent search on PubMed (a database of > 36 million citations for biomedical literature); for example, when "aging and inflammation" term was searched, it yielded a total of 28,994 publications on from year 2000 to 2023.As shown in Figure 1, the number of publications on aging and inflammation increased exponentially, from a mere 103 in 2000 to 3650 in 2023.This increased research on health-related issues continued emphasis on healthy eating and exercise by public health officials, and better awareness among general public for healthy lifestyles have made an impact on consumer trends with respect to food intake (Hill 2022).Furthermore, as Uebersax et al. (2023) indicated, consumers are putting increasing emphasis on the sustainability and environmental impact of various foods in their diets, especially, animal-derived foods.In this regard, emerging consumer trends, to increasingly opt for plant-based food products, present a great potential to expand the utilization of nutrient-dense pulses, such as lentils (Hill 2022;Uebersax et al. 2023).It is noteworthy that lentils are widely consumed in many South Asian and Middle Eastern countries, and the shift towards plant-based protein as meat alternates can potentially expand the consumption of lentils in the developed countries as well.
Figure 2 displays the possible health advantages of consuming processed lentils.The main objective of this article is to present a comprehensive review of consuming lentils, focusing primarily on antioxidant, antidiabetic, anti-inflammatory, cardioprotective, and anticarcinogenic activities and health-related benefits.

| Lentils as a Part of a Complete Healthy Diet
Lentils have gained popularity as a crop and food item in both industrialized and developing nations (Jati, Vadivel, and Biesalski 2013).The seeds have a low-fat content (around 1%), high protein content (about 28%), and high carbohydrate content (63%; 47% starch and 12% dietary fiber [DF]).In addition to minerals like iron, phosphorus, zinc, and calcium, lentils also include vitamins, for example, thiamin, riboflavin, niacin, pantothenic acid, and vitamin B6 (Zeece 2020).Lentils have a comparable overall energy content to other pulses (Stefaniak and McPhee 2015).Because of their high protein content, these seeds can be utilized as a meat extender or alternative (Xu and Chang 2010).Lentil protein is rich in essential amino acids, including leucine, lysine, threonine, and phenylalanine.However, it lacks the sulfur-containing essential amino acids methionine and cysteine.In contrast, proteins found in cereal grains are abundant in methionine but deficient in lysine.Therefore, lentils are commonly accompanied by a mixture of lentil rice or lentil wheat, which offers a comprehensive profile of every essential amino acids, resulting in a complete protein composition (Samaranayaka 2017;Zeece 2020).Additionally, they are utilized in salads, soups, stews, vegetarian recipes, and snack foods (Jati, Vadivel, and Biesalski 2013).

| Major Human Health Risks and Implications
The life style choices, including nutrition, play an important role in maintaining human health across all age groups, from early childhood to old age (Rondini, Barrett, and Bennink 2012).According to the World Health Organization (WHO), every year, noncommunicable diseases (NCDs) kill 41 million people, which is about 74% of all deaths globally.The WHO reports that five factors increase the risk of dying from an NCD, which are the use of tobacco, physical inactivity or lack of exercise, unhealthy diets, excessive alcohol use, and air pollution (WHO 2023).Didinger and Thompson (2022) reported that the most prevalent NCDs are cardiovascular diseases (CVDs), type 2 diabetes, colorectal, breast and prostate cancer, hypercholesterolemia, and obesity.In this regard, diets high in sugar, fat, refined carbohydrate, and sodium are major culprits when it comes to developing NCDs (Rondini, Barrett, and Bennink 2012).Buford (2017) reported that chronic inflammation is consistently a contributing risk factor in most NCDs, especially as we age or grow old.It was also suggested that gut microbiome likely plays a major role in inflammation and development of NCDs, as shown in Figure 3 and that gut dysbiosis (or imbalance) have significant impact on inflammation associated major health conditions.It is a well-recognized fact that choice of diet has a major impact on gut health (Buford 2017).Therefore, healthy eating patterns have major positive implications for the gut microbiome thereby lowering the risk of developing NCDs (Didinger and Thompson 2022).This is an area of health maintenance where increased consumption of food legumes, such as lentils, can play a major beneficial role.

| Health Benefits of Lentils
Inflammation is a natural biological process that helps to protect the body and promote tissue healing.When it persists for an extended period of time and pushes to use anti-inflammatory medicine for a long time, it may eventually trigger the onset of disease like cancer, autoimmune disorders, neurological conditions, or CVD.Natural product-based alternative therapies are becoming increasingly popular in recent years (Stromsnes et al. 2021).Recent studies have demonstrated the presence of bioactive substances such as polyphenols, saponins, and peptides in legumes offer an alternate means of alleviating inflammatory disorders (Juárez-Chairez et al. 2022).Thus, lentils have the potential to combat the unhealthy inflammatory disorders in our body (Alexander et al. 2024).
Food legumes, such as lentils and other legumes, are high in DF and possess a low glycemic index (GI) and hence a low glycemic load as well.Therefore, legumes' consumption can potentially lower the risk of CVDs, noninsulin-dependent diabetes mellitus (type-2 diabetes), and certain cancers, primarily by aiding in satiety indirectly, optimum food intake, and by management of body weight and noninsulin-dependent type-2 diabetes that leads to obesity (Rondini, Barrett, and Bennink 2012).These mechanisms are illustrated in Figure 4. Rondini, Barrett, and Bennink (2012) further noted that dry beans' consumption could have a direct influence on CVD, diabetes mellitus, and certain cancers by affecting insulin sensitivity, hypertriglyceridemia and hyperinsulinemia, as well as by protective actions of some nonnutritive bioactive phytochemicals found in legumes.

| Antioxidant Activity
Oxidative stress refers to the excessive generation of reactive oxygen species (ROS), which disrupts typical cellular processes by causing damage to lipids, proteins, and DNA, which can result in many medical conditions such as diabetes, cancer, atherosclerosis, and neurodegenerative disorders (Pisoschi and Pop 2015).Antioxidants are responsible for shielding cells from oxidative damage and resulting implications.In mammals, a variety of endogenous antioxidant systems combats oxidative stress.These mechanisms are boosted by dietary antioxidants (Lobo et al. 2010).This is the cause of the rise in the use of antioxidantrich foods and dietary supplements in the 21st century.In general, plant-based foods including grains, legumes, fruits, and vegetables are regarded as excellent sources of dietary antioxidants (Jamdar, Deshpande, and Marathe 2017).
Total phenolic content (TPC) and total flavonoid content (TFC) are the processes used to figure out the quantity of phenolic content and flavonoid content, respectively, in the food (Ayele, Akele, and Melese 2022).The ability of phenolic and flavonoid molecules to donate hydrogen atoms to free radicals makes them important antioxidants.They stop or lower the production of free radicals, therefore, alleviating diseases caused by oxidative stress (Aryal et al. 2019).TPC and TFC, as well as antioxidant activity, can be decreased by heat treatment (Mustafa et al. 2022).In one study, two lentil varieties were cooked, and one variety showed a reduction in TPC and antioxidant activity, whereas the other showed no significant change.Cooking even reduced the antioxidant activity of bound phytochemicals of a variety by 24%.The other variety did not show significant changes.Remarkably, in one type, free phytochemical antioxidant activity rose by 10%, while in another type, it increased by 36%.This increase is probably caused by the conjugated phenolics that are released during cooking.This rise in free phytochemicals had no effect on the overall antioxidant activity of lentils since bound phytochemicals accounted for more than 80% of the total antioxidant activity (Han and Baik 2008).The TPC and chemical antioxidant capacities (ferric reducing antioxidant power, FRAP, and peroxyl radical scavenging capacity, PRSC) of cooked lentils were significantly lower than those of raw lentils after conventional boiling, conventional steaming, pressure boiling, and pressure steaming.Conventional steaming exhibited a lower degree of TPC and antioxidant activity loss compared to other heating techniques investigated (Xu and Chang 2009;B. Zhang et al. 2018).There are significant variations between various thermal processing techniques.The differences in the antioxidant characteristics of processed lentils may be occurred because of the synergistic interactions or opposing effects of various oxidative reactions, the extraction of water-soluble antioxidant compounds, the generation or degradation of antioxidant compounds, and higher losses during the processing steps (Xu and Chang 2009).
The phenolic content of lentil was primarily composed of extractable chemical compounds.The process of heating is believed to disturb the integrity of cell membranes and cell walls, resulting in the liberation of lipophilic compounds such as carotenoids and tocopherols from the cellular structure.This, in turn, enhances the efficiency of the extraction process.Consequently, an ideal cooking method should not lead to the depletion of phytochemical antioxidants and should maximize the preservation of the nutritional advantages of eating lentils (Dewanto et al. 2002).
A study conducted by Chakraborty and Bhattacharyya (2014) investigated the impact of boiling and pressure-cooking on the bioactive properties of lentil seeds through in vitro models.The antioxidant activity was determined using the ABTS (2, 2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)), DPPH (1,1-diphenyl-2-picrylhydrazyl), H 2 O 2 (hydrogen peroxide), and hydroxyl radical assays.The antioxidant activity of lentil seeds increased by 24.68% for H 2 O 2 and 147.76% for hydroxyl radical tests but decreased by 22.86% for ABTS and 64.98% for DPPH assays when they were pressure-cooked.When evaluated using the hydroxyl radical test, boiling lentil seeds significantly reduced antioxidant activity, even more than pressure-cooking.In conclusion, pressure-cooked lentils showed higher values in all these antioxidant potentials compared to boil-cooked lentils, which makes pressure cooking an effective method for processing lentils.
Due to the alterations in phenolic compounds and their antioxidant activity caused by the germination process, lentil sprout flour or extract can be used as an organic form of antioxidants in functional meals (López-Cortez et al. 2016).The phenolic content of lentils typically decreases gradually during germination due to the process of leaching into the immersing water, binding with other organic substances, for example, carbohydrates or proteins, and triggering of internal enzymes including hydroxylases and polyphenoloxydases (B.Zhang et al. 2018).TPC, as well as TFC, was greatly enhanced by the sprouting process.During lentil germination, TPC levels increased in the soluble phenolics (SPs) by 26.87% and the insoluble bound phenolics (IBPs) by 34.94% (Yeo and Shahidi 2015).While TFC of IBPs increased by 29.19% during germination, TFC of SPs declined by 21.29%, which is likely because oxidants, particularly ROS generated in the mitochondria, degrade flavonoids.During the first 7 days of germination, the TPC of SPs from green lentils exhibited a significant rise (Cevallos-Casals and Cisneros-Zevallos 2010).Germinated lentils had increased antioxidant activity, as exhibited by up to 21.43% inhibition in DPPH radical scavenging activity assay.Fouad and Rehab (2015) also suggested that the sprouting lentil seeds improves their nutritional content and antioxidant activity.When the seed breaks dormancy, germination may activate defense mechanisms, leading to the production of phenolic compounds and flavonoids.These compounds change with the germination stage and vary based on germination and seed type.The changes in these compounds would indicate seed preparation for adverse conditions (Cevallos-Casals and Cisneros-Zevallos 2010).
A study conducted by Wu et al. (2012) revealed that the increase in SPs that occurs during germination is due to the processes of de novo synthesis and transformation.Glucose is the primary precursor for the production of phenolic compounds.Several important molecular signaling pathways, including the phenylpropanoid pathway, hydrolysable tannin pathway, and shikimate pathway, are responsible for the synthesis and conversion of various phenolic compounds (López-Martínez et al. 2017).Dhull et al. (2023) demonstrated that fermentation using starting cultures such as Aspergillus oryzae, Bacillus subtilis, Aspergillus awamori, and Aspergillus niger, among others, can have both good and negative impacts on the antioxidant potential and polyphenolic compounds (phenolic and flavonoid) of lentils.According to a study by Magro and de Castro (2020), when lentils are fermented, their antioxidant activity increases by approximately 52%, 54%, and 143% in the FRAP, DPPH, and ABTS tests, respectively.Additionally, a strong correlation (r = 0.93) was found between the length of fermentation and the antioxidant activity of water extracts.Following a 24-h fermentation, the DPPH test revealed that the methanolic extract exhibited the highest antioxidant activity.During kinetic fermentation, water extracts showed a linear rise in ABTS test values.
Fermentation has been shown to enhance antioxidant activity in lentils.After fermentation, red lentil extracts showed a maximum rise in TPC of 90.42% while showing a TFC increase of more than three times.The red lentil-fermented extracts demonstrated a maximum 64.05% increase of DPPH scavenging activity when compared to the control or nonfermented extracts.Similar to DPPH, fermentation has demonstrated a favorable impact on the ability to scavenge ABTS.Both TPC and TFC as well as antioxidant activity showed a good correlation with the extracts from fermented lentils.Red lentils showed the strongest association between TFC and DPPH (r 2 = 0.989) (Sadh et al. 2022).In another investigation, the fermentation process of the lentil flour enhanced the antioxidant activity by 18.95% and 3.83% measured through FRAP and ABTS techniques, respectively (Asensio-Grau et al. 2020).Fermentation contributes in enhancing antioxidant compounds and antioxidant capacity by increasing the amount of phenolic compounds and flavonoids during the process.This nonthermal process induces the structural breakdown of plant cell walls, leading to liberation or synthesis of various antioxidant compounds.These compounds can act as free radical terminators, metal chelators, singlet oxygen quenchers, or hydrogen donors to radicals, leading to improved health-linked functionality (Hur et al. 2014;Torino et al. 2013).
Extruded lentil flour exhibited a 10.68% higher concentration of TPC compared to raw lentil flour.Despite having a higher TPC compared to the control, the extrusion procedure reduced its in vitro antioxidant activity by 55.92% in the Ferricyanide/Prussian blue test, 5.43% in the DPPH assay, 59.57% in the β-carotene/linoleate assay, and 39.59% in the thiobarbituric acid reactive substances (TBARS) assay.It likely happened due to the fact that the antioxidant capacity of functional elements in food products depends on the bioactive compounds' concentration along with their composition (Morales et al. 2015).
The effects of several processing techniques (i.e., heating, germination, fermentation, and extrusion) on the antioxidant content of lentils are presented in Table 1.The published findings often show contradictory trends (i.e., an increasing or decreasing impact), which may be related to variations in the lentil types and/ or the analytical procedures employed.

| Antidiabetic Activity
A study by Becerra-Tomás et al. (2018) claims that the risk of developing diabetes was less among the people who ate lentils regularly.Researchers confirmed that cooked lentil lowers blood glucose response using in vitro and in vivo human studies (Ramdath et al. 2017).A persistent drop in acute blood glucose and insulin responses is observed when lentils are consumed.The mechanisms by which lentil seeds lower insulin and postprandial blood glucose responses remain unclear (Clarke et al. 2022).It was found that the mix of the lentil's rapidly digestible starch and resistant starch strongly linked to a lower blood glucose response (Ramdath et al. 2017).
The high amounts of protein, DF, and phenolic compounds present in lentils, together with their strong α-glucosidase inhibitory activity, have been associated with a decrease in the postprandial blood glucose response (Olagunju and Omoba 2021).α-Glucosidase and α-amylase inhibitors play a crucial role in helping diabetics maintain a stable blood sugar levels after meals.Several components of cereals including nonstarch polysaccharides, peptides, lipids, and phenolic compounds have been shown to reduce the activity of α-glucosidase and α-amylase (Gong et al. 2020).
It was reported that cooked lentils were more effective than raw lentils in reducing the increased serum blood glucose level in the diabetic rats.The consumption of these processed lentils resulted in a reduction of up to 26.67% serum blood glucose levels (Al-Tibi, Takruri, and Ahmad 2010).A randomized crossover study including 30 individuals with type 2 diabetes was conducted to investigate the impact of incorporating cooked lentils into their meals.It has been demonstrated that eating cooked lentils for breakfast, a glycemic indexed meal, improves glycemic management in people with type 2 diabetes by reducing total cholesterol (TC) and fasting blood glucose levels.Therefore, it would indicate that a diabetes preventive diet that includes cooked lentils is a successful intervention and management approach (Shams et al. 2008).
Modern societies place an importance on lentil sprouts because of their high content of resistant starch and low glycemic index.The activity of α-amylase inhibitors is decreased and starch bioavailability is increased during germination.Maximum health benefits may be obtained from this easy and costeffective processing method of lentils (Świeca, Baraniak, and Gawlik-Dziki 2013).
Extracts from fermented lentils have been shown to have enhanced antidiabetic effects.The lentil extracts showed a maximum inhibition of around 75% on α-amylase activity as high as 90% inhibition of α-glucosidase activity (Magro et al. 2019).

| Anti-Inflammatory Activity
Inflammation is a well-recognized first line response of defense against pathogens and irritants.However, continuous or severe inflammation can cause tissue damage and a plethora of disorders (B.Zhang et al. 2018).Historically, some inflammatory symptoms have been treated using roasted, milled lentils applied directly to problematic regions; for example, a water paste made from lentils has been employed to heal skin infections and lentils have also been used to cure burns (Sezik et al. 2001;Teklehaymanot et al. 2007).
Phenolics derived from lentils were found to have a dosedependent anti-inflammatory activity over COX-2, IL-1, and IL-6 during inflammation generated by tumor necrosis factor alpha (TNF-α) in Caco-2 cells.The expression of all three of the inflammatory cytokines was markedly decreased by the addition of cooked lentil extract at a concentration of 100-mg powder per mL, since both the overall and specific phenolic compounds of cooked lentils remained intact throughout digestion.In addition, flavonols are the primary phenolic component that have been shown to survive digestion in the gut (B.Zhang et al. 2017).Hence, it is logical to infer that the phenolic compounds found in lentils act as potent antiinflammatory agents.Thus, those at risk for chronic inflammation may benefit from eating cooked lentils that are high in phenolics (B.Zhang et al. 2017).

| Cardioprotective Activity
The consumption of legume seeds has been linked to a decreased risk of CVD and coronary heart disease (CHD).Since lentils are a low-cost, nutrient-dense food source containing many essential bioactive compounds, they could be a component of CVD prevention (Hanson et al. 2016).This legume seeds elevate the amount of cholesterol saturation in bile and decrease TABLE 1 | Effect of different processing on antioxidant content and activities of lentils (↑ = increase, ↓ = decrease, ↕ = both increase and decrease observed, − = no data reported).

Techniques
Abbreviations: ABTS = 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), DPPH = 1,1-diphenyl-2-picryl-hydrazyl, ORAC = oxygen radical absorbance capacity, TFC = Total flavonoids content, TPC = Total phenolic content.a Y. serum cholesterol (Anderson and Major 2002).Incorporating 50 g of cooked lentils into the dietary habits of diabetes patients resulted in a significant reduction in TC levels, while having no effect on high-density lipoprotein cholesterol (HDL-C), lowdensity lipoprotein cholesterol (LDL-C), and triglyceride (TG) levels (Shams et al. 2008).This was due to lentils' polyphenolic activity, which has a positive effect on metabolic illnesses such CHD and CVD (R. H. Liu 2007).Another study indicated that blood TG and TC were significantly reduced in a group of seven males with hyperlipidemic condition who ingested 140 g of cooked dry lentils every day for 4 months, but not LDL-C or HDL-C (Jenkins et al. 1983).
Lentil has a direct impact on vascular structure since they protect the aortic structure from the hypertrophic effects of elevated blood pressure (Hanson, Zahradka, and Taylor 2014).It was shown that rats fed with lentils had considerably lower levels of HDL-C and LDL-C.In those rats, favorable vascular remodeling (arterial function) and greater compliance may have been encouraged by the chemical compounds in lentils, especially polyphenols (Hanson et al. 2016).
Chronic medical conditions, like hypertension, are often linked to a malfunction in the renin-angiotensin-aldosterone system.The conversion of angiotensin I enzyme (ACE) to angiotensin II leads to an elevation in blood pressure due to the increased vasoconstrictor activity (Mentz et al. 2013).One of the best methods for controlling hypertension is thought to be inhibiting ACE (Jamdar, Deshpande, and Marathe 2017).Numerous investigations have shown that phytochemicals have ACE-inhibiting properties (Afonso et al. 2013;Boye et al. 2010;Hussain et al. 2018).The primary components in lentil thought to have potential ACE-inhibitory action are peptides and phenolic compounds (García-Mora et al. 2017;Mamilla and Mishra 2017).
Based on the processing type and condition, lentils have different ACE inhibitory activities, as shown in Table 2.
The ACE inhibitory activity of raw lentil was nearly identical to that of cooked lentil.This was because the raw and cooked lentil crude extracts were not significantly different in their ability to prevent perivascular fibrosis, peripheral vascular remodeling, and angiotensin II-induced hypertension (Y.Zhang, Pechan, and Chang 2018).In an in vitro investigation, the ACE inhibitory action digested lentil sprouts was demonstrated and defined by a half maximal inhibitory concentration in the range of 9.79-11.90g/mL (Peñas et al. 2015).Numerous polyphenols, including flavonoids, anthocyanins, and peptides produced from legumes, can block the formation of ACE (Garcia-Mora et al. 2014;Guerrero et al. 2012).This may explain why lentil sprouts exhibit such high levels of ACE inhibitory action (Peñas et al. 2015).
Fermentation of lentil seeds was shown to release phenolic chemicals that enhanced the extracts' ACE inhibiting properties.The ACE inhibitory efficiency of fermented lentil increased from 24 to 93% during the course of the study (Torino et al. 2013).In a different investigation, fermented lentil extracts outperformed raw lentil in terms of ACE inhibition by up to 3.4-fold (Bautista-Expósito et al. 2018).

| Anticarcinogenic Activity
Pulse consumption is inversely related to the risk of colon cancer, stomach cancer, prostate cancer, and pancreatic cancer death rates (Jain et al. 1999; Rodríguez-García,  Gaforio 2019).Because of their presumed antioxidant activity and bioactive components, particularly lectins and defensins, lentils act to prevent the development of cancer (Arthur, McKenzie, and Beckett 2003;De Mejía and Prisecaru 2005).Various research organizations have initiated several projects to promote awareness about the health-enhancing and nutrient-rich lentils, as more knowledge is acquired regarding their chemopreventive characteristics (Ryland et al. 2010).
Aberrant crypt foci (ACF), which are preneoplastic lesions, were used as surrogate outcomes in chemoprevention trials.In chemoprevention trials, the rat groups that were given different lentil diets showed a significant decrease in multiplicity, ACF count, and crypt size compared to the control diet.Here, these parameters were used as suggestive markers.Rats that were exclusively fed cooked whole lentils exhibited a significant reduction (77.8%) in large ACF, whereas rats that were exclusively given raw whole lentils saw a comparatively lower reduction of just 26.8% (Faris et al. 2009).Since large ACF have been shown to more reliably indicate preneoplastic potential, it has been proposed that lentils, particularly cooked lentils, may have a function of inhibiting the establishment of early aberrant crypts.Cooked whole lentils had the largest percent decrease of the aberrant crypts from large or multicrypt foci, approximately 65% (Faris and Attlee 2017).One possible explanation is the dissolution or production of phenolic chemicals normally found in cell walls or insoluble components of other compounds, where a moderate cooking enhanced the extractability (Shomaf et al. 2011).The inhibitory effect of lentils against ACF has been proven by showing that both raw and sprouted lentils decreased azoxymethane-induced ACF in Fischer 344 male rats, with a significant rise in glutathione, glutathione-S-transferases, and catalase activities.Additionally, compared to other legume grains (i.e., yellow and green peas), lentils showed a stronger chemoprotective effect (Busambwa et al. 2014).

| Other Benefits
Anemia caused by iron deficiency in rats has been demonstrated to be prevented by administering a variety of legumes, including cooked lentils (Ganesan and Xu 2017b).Pulses that have been fermented have lower phytate levels, which improves the availability of iron and other minerals (Sharma et al. 2022).
The effects of red lentil saponin extracts on human fecal microbiota were studied using in vitro colonic fermentation.About 4 g/mL of sapogenin was discovered following the fermentation of lentil extract that had strong antibacterial activity, primarily against Lactobacillus species and lactic acid bacteria.Here, it was found in the form of soyasapogenol B. Researchers concluded that human gut microbiota may convert saponins in lentil extracts into sapogenins, which have a modulatory influence on the proliferation of certain intestinal bacteria (Del Hierro et al. 2020).
Sprouted lentil seeds were shown to contain a new peptide known as "defensin" (Finkina et al. 2008).Antimicrobial activity against bacteria and fungus are just one of the many biological activities exhibited by plant defensins (Stotz, Thomson, and Wang 2009).The purified lentil defensin has antifungal properties, which can inhibit the growth of Aspergillus niger.Defensins have also been shown to alter the activities of HIV-1 reverse transcriptase and the digestive enzymes trypsin and α-amylase, which are all involved in viral replication.Furthermore, it has been demonstrated that several defensins block ion channels and impede protein translation.Therefore, they have been proposed as a possible means of preventing tumor development.In fact, defensin showed antiproliferative effects on a variety of tumor cell lines (Finkina et al. 2008).

| Conclusion
In recent years, lentils have become extremely popular worldwide due to their important contribution to human nutrition as an inexpensive source of both bioactive and non-bioactive nutrients.Various traditional and innovative processing techniques make the seeds of this food legume palatable, substantially reduce or eliminate antinutrients, and enhance their health-promoting properties.Processed lentils have been found to have several beneficial characteristics, such as antioxidant, antidiabetic, anti-inflammatory, cardioprotective, and anticarcinogenic action.The exertion of several phytochemicals and their associated functional qualities has rendered processed lentils a highly commendable functional food option.Therefore, the consumption of processed lentils has potential benefits for those with diabetes, cardiovascular illnesses, and inflammatory problems, as well as have preventive effect against carcinogens.Research efforts are continued for the creation of lentil-based functional food items and nutraceuticals, as this might be a highly cost-efficient method for promoting health.

FIGURE 1 |
FIGURE 1 | Number of publications shown by PubMed when searched for "aging and inflammation" term from years 2000 to 2023.Source: https:// pubmed.ncbi.nlm.nih.gov/ .

FIGURE 2 |
FIGURE 2 | Health benefits of lentil consumption on human body.

TABLE 2 |
ACE inhibitory activity of processed lentils.