It is known that the dietary pattern and macronutrients profile may influence the expression and secretion of inflammatory biomarkers, and the low-grade inflammation is associated with the manifestation of noncommunicable chronic diseases. Therefore, this review aimed to present and discuss the role of dietary patterns and macronutrients on the variation of inflammatory markers related to NCD risk. Scientific evidences within the last five years based on clinical trials, case-controls, cohorts, and cross-sectional studies indicate that normocaloric, carbohydrate-moderated, low-glycemic index, protein-moderated, monounsaturated and polyunsaturated fatty acid-rich, omega-3, and low-saturated fat diets display positive effects on the inflammatory state, both in healthy individuals and in those with cardiovascular risk, although the second group seems to benefit more from changes in the dietary profile.
Low-grade inflammation refers to a series of metabolic and physiological modifications with proinflammatory cytokines and increased oxidative stress [
The dietary pattern may be defined as a combination of foods frequently consumed by individuals and population groups [
Indeed, some dietary patterns, such as the Mediterranean and DASH (Dietary Approach to Stop Hypertension) diets, are associated with an improved weight control and lower incidence of NCD [
On the other hand, the impact of the distribution of macronutrients—carbohydrates, proteins, and lipids—on the inflammatory state has been extensively investigated [
For this review, the electronic databases PubMed (National Library of Medicine, Bethesda, MD) and ScienceDirect were researched. The following keywords were used for article search: “dietary fat”; “fatty acids,” “omega-3,” “saturated fat,” “olive oil,” “dietary patterns,” “dietary protein,” and “dietary carbohydrate” always combined with the MeSH terms “inflammation” or “inflammatory markers.” The search was limited to English studies published between March 2012 and April 2017. The inclusion criteria considered original studies published within the last 5 years, in English, which assessed the relation of dietary pattern and macronutrients profile on the variation of inflammatory biomarkers, in observational or interventional study designs. Review papers, editorials and book chapters, case reports, studies with animals or cells, studies that did not aim to evaluate the inflammation, studies that used supplements with registered mark, and studies that assessed the relation between inflammation and diseases other than diabetes, dyslipidemia, metabolic syndrome, obesity, and cardiovascular diseases were excluded from the present review.
Initially, 9429 papers were found. Of these, 9183 papers were excluded after title and abstract screening, and 246 papers were fully read. Of these, 40 papers met the inclusion criteria and were kept for this review (Table
Paper selection stages and inclusion and exclusion criteria for the systematic review.
Stages | Inclusion and exclusion criteria |
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1 |
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PubMed | 4869 | |
ScienceDirect | 4560 | |
Total number of studies identified | 9429 | |
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2 |
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Review papers | 1510 | |
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1277 | |
Editorials and book chapters | 1752 | |
Studies that did not aim to evaluate the inflammation | 3073 | |
Studies that used registered mark supplements | 12 | |
Studies that assessed pregnancy diet and newborn’s inflammation | 6 | |
Studies in which inflammation was related to diseases other than diabetes, dyslipidemia, metabolic syndrome, obesity, and heart diseases | 1329 | |
Studies that did not assess the dietary pattern in general | 178 | |
Duplicated | 46 | |
Total number of papers excluded | 9183 | |
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3 |
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246 |
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4 |
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No results regarding inflammatory markers, only of other cardiovascular risk markers | 187 | |
Results regarding gene expression only | 19 | |
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5 |
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40 |
The dietary patterns analysis helps to understand the factors that contribute to NCD [
Among
On the other hand, the cluster and factor analyses are the most frequently used
Regardless of the approach used, it is a consensus that dietary patterns deemed healthy displays as an inverse relationship with the concentrations of inflammatory biomarkers [
In this context, Corley et al. [
On the other hand, in the study by Bédard et al. [
In turn, the occidental dietary pattern, characterized by the excessive intake of calories, salt, fat, and sugar, has been associated with the increase of low-grade inflammation and with the development of the NCD [
A similar effect was observed in the study by Kong et al. [
Similarly, when considering the foods altogether, we can stablish how anti- or proinflammatory a diet can be [
The foods included in a diet may directly influence the individual’s health. Fruits and vegetables are foods that, when consumed on a daily basis in an adequate amount, are capable of reducing the oxidative stress and low-grade inflammation markers [
Lee et al. [
It is known that fruits and vegetables have various bioactive and antioxidant compounds [
The studies presented in this review (Table
Studies that assessed the effect of dietary patterns on the chronic subclinical inflammation.
Reference | Study type | Population | Methods | Results |
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Ozawa et al. [ |
Cohort | 5083 British overweight adult individuals | Validated FFQ; determination of factorial inflammatory loadings for food groups and identified two dietary patterns (pro- or anti-inflammatory) | Dietary pattern considered inflammatory characterized by red meat, fried foods, and lower ingestion of whole grains: ↑ IL-6 |
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Kuczmarski et al. [ |
Cohort | 2176 American adult individuals | 24 h recalls; identification of the most consumed foods was grouped according to the similarity of their components and new dietary patterns were created; cluster analysis for definition of ten groups | All patterns displayed elevated (>3 mg/L) CRP, whereas the highest average was that of the “frozen food” pattern (7.2 ± 1.4 mg/L) |
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Corley et al. [ |
Cross-sectional (from a cohort) | 792 Scottish elderly eutrophic individuals | Self-applied FFQ; dietary patterns as Mediterranean and conscious (high intake of fruits and carrots and low intake of embedded foods, eggs, pork, and liqueurs) | Highest score of the conscious dietary pattern and higher ingestion of fruits: ↓ CRP; highest score of the Mediterranean dietary pattern: ↓ fibrinogen |
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Kong et al. [ |
Case-control | 45 overweight and obese adults | 7-day (for overweight and/obese) and 3-day dietary record (for the control group); three dietary patterns were determined: Group 1 (less healthy, high consumption of beverages and foods high in sugar, fat, and salt); Group 2 (healthier, with higher consumption of water, yogurt, cereals, eggs, and nuts); Group 3 (healthier, with a fiber-rich diet, lower consumption of sugar, fruits, yogurt, and soups) | Group 3: ↓ sDC14, followed by Group 2 and Group 1; Group 3: ↑ DC163; no differences between the groups for the LPS, CRP, and IL-6 concentrations; higher consumption of fruits, green vegetables, and soups ↑ DC163 |
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Lee et al. [ |
Cross-sectional | 7574 eutrophic adult individuals | FFQ; 4 dietary patterns determined as standard: fruit, vegetable, meat, and coffee, according to the prevailing food | Highest score for the “vegetable” pattern: ↓ CRP; highest score for the “vegetable” pattern: ↑ ingestion of antioxidants |
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Bédard et al. [ |
Clinical trial | 70 Canadian, overweight, adult individuals, with risk of cardiovascular disease | Four weeks following the Mediterranean pattern | Male individuals who displayed CRP values > 3 mg/L displayed a reduction over time; male individuals who displayed reduced CRP values (<3 mg/L), displayed an increase over time; no beneficial effect of the Mediterranean diet was observed for both genders |
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Abete et al. [ |
Case-control | 51 healthy individuals and 51 individuals with history of stroke | FFQ; 2 dietary patterns determined as “healthy” and “not healthy” | Healthy individuals displayed greater adherence to the healthy dietary pattern, as well as ↓ CRP and ↓ leukocytes |
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McGeoghegan et al. [ |
Cohort | 1531 healthy and diabetic individuals | 4-day dietary record during 4 years; 2 dietary patterns determined: “1”—higher antioxidant and anti-inflammatory loads; “2”—lower antioxidant and anti-inflammatory loads | Dietary pattern “1” was inversely related to the CRP concentrations |
FFQ: Food Frequency Questionnaire; IL-6: interleukin 6; CRP: C-reactive protein; sDC14: differentiation cluster 14; DC163: differentiation cluster 163; LPS: lipopolysaccharide.
The proportion and type of fats included in the diet influence the degree of inflammation and the risk of NCD. In this context, the intake of polyunsaturated fatty acids (PUFA), particularly the long-chain ones from the w-3 series (n-3 PUFA), is related to the reduction of the risk of cardiovascular diseases and death due to its anti-inflammatory potential [
Saturated fatty acids (SFA), on the other hand, favor the increase of inflammation. Most studies included in this review related the consumption of SFA to the increase of inflammatory markers and NCD. Kantor et al. [
Silver et al. [
With respect to the linolenic acid, an intervention with type-2 diabetics resulted in reduction in the IL-2 concentrations and TNF-
Accordingly, the beneficial mechanism of the linoleic acid (n-3 series) has been related to its derivatives, the EPA C20 : 5 n-3 and DHA 22 : 6 n-3 acids, which have a higher anti-inflammatory effect than the derivatives of the arachidonic acid (AA n-6 PUFA) derived from the linoleic acid (n-6 series). Such a effect was reported in a study with adults, in which an increase was reported in the formation of EPA and DHA after four months of supplementation (1.4 g/d) in comparison with the placebo group (soy oil), although with no changes in AA metabolites [
However, investigations about the effect of n-3 lipids on NCD-related biomarkers reported contradictory findings. The cardiometabolic risk of the sample population seems to influence the results, as the beneficial effects are more evident in individuals with more than one risk factor, rather than excessive body fat alone [
The differences observed in the inflammatory profile may be related to variations in the intervention time and in the supplemented daily dose. The daily doses used varied between 1 and 6.6 g/d, whereas doses above 3 g/d were less common. Another aspect worth considering is the origin of fatty acids of the n-3 series, which may be plant or sea-derived. Only one study included in this review, conducted by Dewell et al. [
Furthermore, the relation between linoleic (CLA) and linolenic (LNA) acid intake is very important for homeostasis [
In its turn, the extravirgin olive oil, mainly composed by MUFA (w-9 series)—oleic acid—has reduced the risk of NCD when used as supplement or consumed within the context of healthy dietary patterns [
Nevertheless, the concentration of phenolic compounds in the oil, capable of reducing the synthesis of AA and cyclooxygenase enzymes 1 and 2 (COX-1 and COX-2), may be a key factor in its potential to reduce inflammatory markers. Camargo et al. [
The large number of studies devoted to investigate the relation between lipids and inflammation highlights the importance of this macronutrient to the modulation of several inflammatory biomarkers (Table
Studies included in this review, which assessed the effect of lipids on the chronic subclinical inflammation.
Reference | Study type | Population | Methods | Results |
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Kantor et al. [ |
Retrospective cohort | 8177 elderly, institutionalized Americans, included in the 1999–2004 cycles of the National Health and Nutrition Examination Survey | BMI classification: eutrophic < 25 kg/m²; overweight ≥ 25 < 30 kg/m²; obese ≥ 30 kg/m² | Lower SFA intake and utilization of fish oil were associated with ↓ CRP in eutrophic and overweight groups, but not in obese |
24 h recall | ||||
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Krysiak et al. [ |
Randomized, controlled clinical trial | 101 (66 M/35 W) overweight, hypertriglyceridemic Polish adults | Group 1: placebo | Group 2: ↓ IL-2, IFN- |
Group 2: bezafibrate (200 mg twice a day) | Bezafibrate was better than n-3 in inhibiting low-grade inflammation | |||
Group 3: n-3 (1 g, twice a day) | ||||
Duration: 12 weeks | ||||
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Dewell et al. [ |
Randomized, controlled clinical trial | 100 obese American adults, with metabolic syndrome | Group 1: vegetable-derived n-3 | ↔ sICAM-1, IL-6, and monocyte chemoattractant protein in all three groups |
Subgroup 1: low dose (2.2 g/d of n-3) | No beneficial independent effect of dose or source | |||
Subgroup 2: high dose (6.6 g/d of n-3) | ||||
Group 2: sea-derived n-3 | ||||
Subgroup 1: low dose (1.2 g/d) | ||||
Subgroup 2: high dose (3.6 g/d) | ||||
Group 3: placebo | ||||
Duration: 8 weeks | ||||
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Malekshahi Moghadam et al. [ |
Double-blind, controlled, randomized clinical trial | 84 (42 M/42 W) overweight Iranian adults and elderly with DM for at least 2 years | Group 1: 3 n-3 capsules/day (EPA 1.548 mg; DHA 828 mg; other n-3 338 mg) | Group 1: ↓ IL-2 and TNF- |
Group 2: 3 placebo capsules (sunflower oil 2100 mg) | ↔ CRP | |||
Duration: 8 weeks | ||||
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Kratz et al. [ |
Double-blind, controlled, randomized clinical trial | 24 (8 M/16 W) overweight, or level-1 obese American adults | Group 1: n-3-rich diet (3.5% of diet energy) | ↔ Gene expression of inflammatory mediators by adipose tissue |
Group 2: diet poor in n-3 (0.5% of energy diet) | ↔ IL-6, MCP-1, TNF receptors 1 and 2, and CRP | |||
Duration: 14 weeks (ad libitum by 12) | ||||
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Rajkumar et al. [ |
Randomized, controlled clinical trial | 60 (30 M/30 W) overweight Indian adults | Group 1: placebo | Group 2: ↓ CRP |
Group 2: omega-3 (EPA 180 mg/d, DHA 120 mg/d) | Group 4: more pronounced effect in CRP reduction | |||
Group 3: probiotic VSL # 3 (112.5 × 109 UFC) | ||||
Group 4: omega-3 (EPA 180 mg/d, DHA 120 mg/d) and probiotic VSL # 3 (112.5 × 109 UFC) | ||||
Duration: 6 weeks | ||||
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Cipollina et al. [ |
Double-blind, controlled, randomized clinical trial | 45 overweight American adults, with EPA + DHA consumption ≤ 300 mg/d | Group 1: capsules containing 1.4 g/d of EPA + DHA | Group 1: ↑ DHA and EPA, no significant modulation in the levels of arachidonic acid metabolites |
Group 2: Placebo (soy oil) | ||||
Duration: 4 months | ||||
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Nigam et al. [ |
Double-blind, controlled, randomized clinical trial | 316 (221 M/105 W) overweight American adults and elderly with symptomatic paroxysmal or persistent FA | Group 1: fish oil (4 g/d) | Group 1 ↔ inflammation or oxidative stress ↓ CRP in a similar degree between the groups, after 6 months (CRP 11% versus 11% for fish oil versus placebo, respectively) |
Group 2: placebo | ||||
Duration: 271 ± 129 days | ||||
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Ito et al. [ |
125 (64 M/61 W) obese Japanese adults, with ( |
Group 1 (treatment group—dyslipidemic): diet (isocaloric, normoproteic, and normolipidemic), EPA 1.8 g/d | DHA/AA and DGLA/AA ratios were higher in dyslipidemic obese, in comparison with the nondyslipidemic | |
Group 2 (control—dyslipidemic): diet (isocaloric, normoproteic, and normolipidemic), no EPA. | Group 1: ↓ CRP, ↓ DLGA/AA ratio | |||
Group 3 (control—nondyslipidemic): no intervention | ||||
Duration: 3 months | ||||
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Lee et al. [ |
Double-blind, controlled, randomized clinical trial | 14 obese American with metabolic syndrome and 45 adults and elderly type-2 diabetics | Group 1: corn oil (4.02 g/d) | Group 2: ↑ serum ALA |
Group 2: botanical oil (BO) (6.28 g/d) | Group 3: ↑ EPA and DHA; ↓ DGLA and AA | |||
Group 3: fish oil (FO) (7.64 g/d) | Groups 1 and 2 were associated with increased levels in biomarkers related to type-2 diabetes and metabolic syndrome | |||
Duration: 8 weeks | ||||
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Camargo et al. [ |
Randomized, cross-over clinical trial | 49 individuals (19 M/30 W) with metabolic syndrome | Group 1: breakfast rich in olive oil with high phenolic content (398 ppm) | Group 1: higher IL-6, IL-1, CXCL reduction |
Group 2: breakfast rich in olive oil with intermediate phenolic content (149 ppm) | ||||
Group 3: breakfast rich in olive oil with low phenolic content (70 ppm) | ||||
Duration: 2-hour postprandial | ||||
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Ceriello et al. [ |
Randomized, controlled clinical trial | 24 diabetics (17 M/7 W) | Group 1: Mediterranean diet (olive oil) | Group 1: ↓ IL-6, sICAM-1, PGF2 |
Group 2: hypolipidemic diet | ||||
Duration: 3 months | ||||
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Casas et al. [ |
Randomized, controlled clinical trial | 164 (77 M/87 W) individuals with cardiovascular risk | Group 1: Mediterranean diet + 50 ml extravirgin olive oil | Groups 1 and 2: ↓ CRP, IL-6, sICAM |
Group 2: Mediterranean diet + 30 g/d of oilseeds | ||||
Group 3: hypolipidemic diet | ||||
Duration: 12 months | ||||
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Darghosian et al. [ |
Double-blind, controlled, randomized clinical trial | 190 (109 M/81 W) overweight American adults and elderly with FAR | Group 1: n-3 (4 g/d) | ↔ IL-6, IL-8, IL-10, TNF- |
Group 2: placebo | ||||
Duration: 6 months | ||||
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Krantz et al. [ |
Double-blind, controlled, randomized clinical trial | 72 (22 M/42 W), mainly Latin (71%) obese adults and elderly | Group 1: 3.36 g/d of n-3 (EPA/DHA) | Group 1: nonsignificant CRP reduction |
Group 2: placebo | ↔ Inflammation | |||
Duration: 3 months | ||||
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Itariu et al. [ |
Randomized, controlled clinical trial | 55 (9 M/46 W) level-3 obese American adults and elderly | Group 1: 3.36 g/d of n-3 (EPA/DHA) | Group 1: ↓ gene expression of inflammatory markers in subcutaneous adipose tissue |
Group 2 (placebo): 3.36 g/d of butter | ↓ IL-6 | |||
Duration: 8 weeks | ↑ anti-inflammatory eicosanoids in visceral adipose tissue | |||
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Lesná et al. [ |
Double-blind, controlled, randomized clinical trial | 15 overweight or obese adult American women, in postmenopause | 2- to 3-week cross-over interventions, with 1-week interval between them | Change from Group 1 to Group 2: ↓ CRP and IL-18 (the latter was not significant) |
Group 1 (animal-derived SFA): 42% of TCV | ||||
Group 2 (vegetable-derived PUFA): 40% of TCV | ||||
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Silver et al. [ |
Double-blind, controlled, randomized clinical trial | 144 level-1 obese adult American women in postmenopause | Women received Group 1 diets during 2 weeks | ↓ IL-1 |
Group 1 (DHL): high-fat diet (50% of TCV); 1/3 SFA, 1/3 MUFA, 1/3 PUFA) | Compared to DHL + P, DHL + S had higher effect on the IFN- | |||
Hence, they were randomized into the following groups for 14 weeks: | MUFA/PUFA/SFA in the diet changed markers to CVD | |||
Group 2 (DHL-P): DHL + placebo | ||||
Group 3 (DHL-S): DHL + stearate (9 g/d) | ||||
Group 4 (DHL+O): DHL + oleate (9 g/d) | ||||
Group 5 (DHL+L): DHL + linoleate (9 g/d) | ||||
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Agh et al. [ |
Double blind, controlled, randomized clinical trial | 45 men with coronary artery disease | Group 1: n-3 (720 mg EPA, 480 mg DHA) | Group 1: ↓ CRP |
Group 2: placebo (edible paraffin) | ||||
Duration: 8 weeks | Group 2: ↔ CRP |
M: men; W: women; BMI: body mass index; SFA: saturated fatty acids; CRP: C-reactive protein; n-3: omega-3; sICAM-1: soluble intercellular adhesion molecule-1; IL: interleukin; IFN-
Proteins are the macronutrients of greatest thermogenic effect due to their high cost of metabolic synthesis, hydrolysis, gluconeogenesis, and excretion as urea [
The effects on human health arising from the ingestion of several protein types have been investigated, although their association with metabolic diseases is still conflictive [
Currently, iron has been reported as a promoter of atherosclerosis due to its ability to produce free radicals [
Azadbakht and Esmaillzadeh [
Dairy products are also a food group deemed as an important protein source. Hence, Zemel et al. [
Amini et al. [
In addition to the studies that assessed the amount and quality of protein associated with the NCD and chronic subclinical inflammation, the quality and amount of carbohydrates or the glycemic index have been highlighted within the scientific literature (Table
Studies addressing the effect of proteins, carbohydrates, and glycemic index on the chronic subclinical inflammation.
Reference | Study type | Population | Methods | Results |
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Azadbakht et al. [ |
Cross-sectional | 482 female teachers from Tehrani, between 40 and 60 years old | (i) Usual dietary intake was assessed through a semiquantitative FFQ with 168 items | PCR plasma concentrations were higher in individuals from higher quintiles of red meat consumption, even after model fit |
(ii) FFQ foods were classified into 41 food groups, based on the nutrient profile, culinary, or specific use | ||||
(iii) Red meat category was defined by the sum of processed meat (sausages and hamburgers), red meat (beef and lamb), and organ meat (liver, kidney, and heart) | ||||
(iv) Blood samples: assess inflammatory markers | ||||
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Vallianou et al. [ |
Cross-sectional | 490 middle-aged Caucasian adults, apparently healthy | (i) Validated semiquantitative FFQ, with 76 food items |
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BMI: between 26 and 27 kg/m² | (ii) Food items were grouped according to the protein content: nonheme (dairy products and eggs), heme (meat and by-products, fish and seafood), and vegetable protein |
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(iii) Blood samples taken after 12 hours of fasting: cystatin C, CRP, white cells, uric acid, and platelets as inflammatory parameters |
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Montonen et al. [ |
Cross-sectional | 2198 German individuals from the EPIC cohort (836 M, between 40 and 65 years old; 1362 W, between 35 and 65 years old) | (i) Usual intake of previous year was assessed through a self-applied FFQ, with 148 items | (i) Inverse association of whole bread consumption with [CRP] and [GGT] |
BMI: between 25 and 26 kg/m² | (ii) Frequency of consumption was requested in 10 categories, and the amount of consumption was calculated in grams | (ii) Direct association of red meat consumption with [CRP] and [GGT] | ||
(iii) Reproducibility after 6 months: high for red meat intake and moderate for whole bread intake | ||||
(iv) Intake of these foods was divided in quintiles | ||||
(v) Blood samples: assess CRP was inflammatory parameter and GGT for oxidative stress | ||||
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Cocate et al. [ |
Cross-sectional | 296 men, working at the Universidade Federal de Viçosa (Brazil), between 40 and 59 years old | (i) Usual dietary intake was assessed through an FFQ, validated for the Brazilian population | (i) Ox-LDL concentrations displayed positive correlation with red meat consumption and the saturated fat in it |
(ii) The red meat group was composed of lean meat, high-fat meat, ground beef, lean pork meat, high-fat pork meat, and bacon | ||||
(iii) The white meat group was composed of chicken with skin, skinless chicken, and fish | ||||
(iv) Blood samples after 12 h of fasting: assess ox-LDL | ||||
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Schwedhelm et al. [ |
Cross-sectional | 553 individuals from the Bavarian Food Consumption Survey II group, between 18 and 80 years old | (i) Dietary intake, including meat intake, was assessed through three 24 h recalls (2 in weekdays and 1 in the weekend) | (i) Processed meat consumption displayed positive association with IL-6 after adjusting for fruit and green vegetable consumption, except when there was BMI addition to the model |
(ii) Red meat: beef, veal, pork, mutton or lamb, and domestic and game rabbit | (ii) Processed meat consumption was positively associated with TNF- | |||
(iii) Processed meat: ready-made meat or meat preserved by salting, smoking, curing, marination, or cooking | (iii) Consumption of nonprocessed red meat was inversely associated with TNF-R1 and TNF-R2 | |||
(iv) Blood samples: assess CRP, IL-6, total TNF- | ||||
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Arya et al. [ |
Randomized cross-over | 10 (6 M/4 W) healthy individuals between 19 and 38 years old | Before testing diets: 10 h fasting | Fat meat is more proinflammatory than lean meat: |
BMI: between 18 and 26.5 kg/m² | Types of meals: | (i) 1 h postprandial: [CRP], [TNF- | ||
(i) Lean meat (<4% fat, whereas <1% saturated fat) + 75 g of boiled potato + 50 g of peas | (ii) 2 h postprandial: [TNF- | |||
(ii) Fat meat (25–30% fat, whereas 40% saturated fat + 75 g of boiled potato + 50 g of peas | ||||
Participants were categorized in 2 groups of 5, and each group received a type of meal. After 6–10 days, group meals were changed | ||||
Blood samples 1 h and 2 h postprandial: assessment of CRP and TNF- | ||||
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Zemel et al. [ |
Randomized cross-over | 20 healthy adults (14 M/6 W), professors, employees, and students at the University of Tennessee, with mean age = 31 years | (i) The study displayed 2 weight-maintenance diets: one for the overweight group and the other for the obese group | Skimmed milk smoothie significantly decreased circulating TNF-α (15%) and IL-6 (13%), whereas soybean diet had the opposite effect |
BMI: 10 overweight (25.0–29.9 kg/m²) and 10 degree-1 obesity (30–34.9 kg/m²) | (ii) Both diets offered ≈35% fat, ≈49% carbohydrates, 16% protein, and 8–12 g/d of fiber; the placebo diet was based on soy protein and the testing diet on skimmed milk protein | MCP-1 concentrations were significantly lower in individuals who consumed skimmed milk smoothie, whereas the soy smoothie caused an increase in MCP-1 | ||
(iii) Both groups were categorized in two additional ones and each subgroup received for 28 days: 3 soy protein smoothies or 3 skimmed milk protein smoothies. After 28 days, subgroups meals were changed for additional 28 days | Skimmed milk smoothie resulted in a significant increase in circulating adiponectin (20%), whereas soy smoothie resulted in its decrease | |||
Each smoothie shake contained 170 kcal, 10 g of proteins, 1 g of fat, and 30 g of carbohydrates | CRP exhibited an global treatment effect, which resulted in a significant reduction (57%) through the ingestion of skimmed milk smoothie | |||
(iv) Blood samples: assess inflammatory markers | ||||
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Holmer-Jensen et al. [ |
Randomized case-control | 11 Caucasian middle-aged obese individuals (3 M/8 W), BMI: ≥30 kg/m² |
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Standard dietary intake: | CCL5 was higher in the postprandial period of 30 min than in the basal, for all protein sources | |||
(i) 56% carbohydrates, 24% fat, and 20% proteins | After 4 h postprandial: | |||
(ii) 1673 kcal women and 2151 kcal men blood sample after 12 h fasting testing diet intake for 20 min | Lower CCL5 for whey protein than to cod and casein protein | |||
(iii) Hypercaloric: 19% carbohydrates, 66% fat, and 15% protein: 1188–1191 kcal | Lower CCL5 for gluten protein than to cod protein | |||
(iv) 45 g white bread, 100 g butter, 45 g of protein (mixed with the meal or the water, according to the source) blood samples after 4 h postprandial: analyze inflammatory markers |
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MCP-1 was lower in the postprandial period of 30 min than in the basal, for all protein sources | ||||
After 4 h postprandial: | ||||
Higher MCP-1 for whey protein than for cod and gluten protein | ||||
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Gögebakan et al. [ |
Randomized case-control | 773 European obese adults, with mean age of 41 years | After 8 weeks under low-caloric diet (800 kcal/day), were selected those whose weight loss is ≥8%, and the LC diet was applied again | (i) After low-caloric diet, there was a decrease in [CRP] |
BMI: 34 kg/m², from the Diogenes project | Diet composition: | (ii) During the dietary intervention, there was a decrease in [CRP]: > in the LGI than in the HGI group and > in the LP than in the HP group | ||
(i) LP (10–15% energy) + LGI | (iii) LGI group displayed an additional reduction of 15% in [CRP] | |||
(ii) LP + HGI | (iv) After the 26 weeks, the LGI and LP groups displayed significant reduction in [CRP] with respect to the HGI and HP groups | |||
(iii) HP (23–28% energy) + LGI | ||||
(iv) HP + HGI | ||||
(v) Control | ||||
(a) There should be ≠ 15 points from HGI to LGI | ||||
(b) Guidance for healthy choices | ||||
Blood samples after 10 h fasting: CRP assessment as inflammatory parameter | ||||
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Damsgaard et al. [ |
Randomized case-control | 253 European children and adolescents, from 5 to 18 years old, with overweight parents, from the Diogenes project | Diet composition: | Changes in [CRP] after intervention were greater in the LGI than in HGI, but significance was lost after Bonferroni correction, which may explained by the families with lower adherence to the diets |
4.8% W and 4.2% M, from 10 to 18 years old → MS | (i) LP (10–15% energy) + LGI | |||
(ii) LP + HGI | ||||
(iii) HP (23–28% energy) + LGI | ||||
(iv) HP + HGI | ||||
(a) There should be ≠ 15 points from HGI to LGI | ||||
(b) Guidance for healthy choices | ||||
Blood samples after 4 h fasting: CRP assessment as inflammatory parameter | ||||
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Raatz et al. [ |
Randomized cross-over | 55 American eutrophic and obese individuals (16 M/39 W), from 20 to 80 years old | (i) Individuals received the 50 g of three types of sugar to be consumed diluted in water | Basal levels: |
BMI: 18 to 39.9 kg/m² | (ii) Each type of sugar was consumed during 2 weeks, with a 2- to 4-week period between treatments | (i) [PCR] and [IL-6] were significantly greater in TGI | ||
(iii) Blood samples after 10 h fasting: days 0 and 15 from each experimental period, to assess CRP and IL-6 as inflammatory parameters | Posttreatment: | |||
(i) [PCR] and [IL-6] were significantly greater in TGI | ||||
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Amini et al. [ |
Randomized case-control | 56 Iranian women, between 20 and 46 years old, BMI ≥ 25 kg/m², engaged in physical activities three times a week, 60 minutes per session | Female volunteers were grouped equally and randomly in two diet groups: | There was a marginally significant decrease in CRP levels after intervention, both in the HP and LP diets |
(i) HP diet: 45% carbohydrates, 25% protein, and 30% fat | ||||
(ii) LP diet: 55% carbohydrates, 15% protein, and 30% fat | ||||
(iii) All of them displayed a reduction of 500 kcal from the conventional diet | ||||
Dietary intake was determined by a food record applied on baseline and every 2 weeks, referring to 3 days of the week | ||||
(iv) HP and LP diets were provided in an 8-week period | ||||
(v) Blood samples: assess CRP as inflammatory parameter |
BMI: body mass index; kg/m²: kilogram per square meter; FFQ: Food Frequency Questionnaire; CRP: C-reactive protein; M: men; W: women; CCL5: CC chemokine ligand-5; MCP-1: monocyte chemoattractant protein-1; MS: metabolic syndrome; GI: glycemic index; CVD: cardiovascular disease; LP: low protein; LGI: low glycemic index; HGI: high glycemic index; HP: high protein; kcal: kilocalorie; GGT: gamma glutamyl transferase; IL-6: interleukin 6; GI: glucose intolerance; ox-LDL: oxidized low-density lipoprotein; TNF-
For example, Montonen et al. [
With respect to simple carbohydrates, its elevated consumption is worrying, especially when added in foods and drinks, thus favoring the inflammatory state and negative health effects. The World Health Organization (WHO) recommends that children and adults reduce the sugar intake to <10% of total energy, and that this value should be lowered over lifetime [
In this context, a study with eutrophic individuals, aged between 20 and 80 years, which aimed to determine the effect of the chronic fructose (55%) consumption, sucrose, and honey on glucose-tolerant (GT), as well as glucose-intolerant (GI) individuals, reported that the GI group displayed serum CRP concentrations > 3 mg/L before and after intervention, and these values were lower to those observed in the acute inflammation, which may indicate an increased risk of cardiometabolic disease [
Another study with obese individuals reported higher CRP and lower adiponectin, following hyperglycemic (59–67% of TCV) diets [
In turn, with respect to the studies with adults, which associate the ingestion of protein and carbohydrates/glycemic index to the ingestion of hyperproteic (10–15% of TCV), HP (23–28% of TCV) [
Studies that assessed the effects of GI and protein intake on the inflammatory markers in children are scarce. The study Diet, Obesity, and Genes (Diogenes), found an increase in body fat in children who consumed a HP + HGI diet, whilst the percentage of overweight children decreased in the group who consumed the HP + LGI test diet [
Thus, it is possible to acknowledge that the lower consumption of protein from red meat and the higher consumption of proteins from vegetables, white meat, and milk displayed beneficial health effects and may lead to the decrease of inflammatory markers. However, there is still lack of consistent information about the effect of protein origin and amount on the inflammation, particularly in healthy people. With respect to GI and carbohydrates, results indicate that the moderate ingestion of carbohydrate, as well as of food with LGI, may have a beneficial effect on the metabolic and inflammatory states in obese individuals, while in children and adolescents, the LGI displayed an inverse effect.
From this literature review, we reiterated the importance of a varied diet, rich in natural foods and poor in processed foods, such as some previously known patterns (Mediterranean and DASH diets) to prevent and improve low-grade inflammation. With respect to the macronutrients, the provided consumption of PUFAs and MUFAs, as replacements for SFA (moderate intake of carbohydrates, in particular the ones with low glycemic index, and the consumption of proteins, in particular the ones of plant origin and white meats), may positively influence the modulation of low-grade inflammation and, consequently, has a protective effect for the development of the NCD.
However, further studies are necessary, in order to evaluate the inflammatory response to the consumption of dietary patterns or intake of specific macronutrients in different situations of weight, age, and metabolic condition, for a better understanding of the most appropriate dose-response.
Helen Hermana Miranda Hermsdorff and Sylvia do Carmo Castro Franceschini are fellows of National Council for Scientific and Technological Development (CNPq) Research Productivity. The funding received did not lead to any conflicts of interest. Also, there are no other conflicts of interest regarding the manuscript.
The authors are grateful to Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) for the grants conceded to Brenda Kelly Souza Silveira, Thatianne Moreira Silva Oliveira, and Patrícia Amaro Andrade. This review is supported by the FAPEMIG (State of Minas Gerais, Brazil) and CNPq, related to research team’s projects. HHM Hermsdorff and SDCC Franceschini are CNPq fellows.