Nutritional Genomics and the Role of the Mediterranean Diet in Cardiovascular Disease

A dietary pat­tern is made up of dif­fer­ing amounts of foods and bev­er­ages that all work col­lec­tively and in syn­ergy to pro­vide over­all health ben­e­fits. Rather than look­ing at sin­gle nutri­ents as solu­tions to health prob­lems, researchers have begun explor­ing the sum of com­po­nents offered by var­i­ous dietary pat­terns. Since an individual’s dietary pat­tern is an envi­ron­men­tal ele­ment that they are exposed to each day, yet it is within their con­trol to alter, a dietary pat­tern could be the most crit­i­cal choice for pre­vent­ing chronic lifestyle dis­eases and pro­mot­ing healthy aging.

The Mediterranean diet (MedDiet) con­tains foods that are high in phy­to­chem­i­cals, namely fruits, veg­eta­bles and the abun­dant daily con­sump­tion of olive oil (OO), which have all been shown to reduce symp­toms and pre­vent the risk of hyper­ten­sion, cho­les­terol, stroke and car­dio­vas­cu­lar risk. The addi­tion of OO, con­tain­ing more than 36 phe­no­lic com­pounds, makes the MedDiet pat­tern very unique and con­tributes sig­nif­i­cantly to its over­all health attrib­utes.
See Also:Olive Oil Health Benefits
However, although the MedDiet is one of the widest stud­ied dietary pat­terns, the mech­a­nisms under­ly­ing its ben­e­fi­cial effects on health are still largely unknown, which is where nutri­tional genomics stud­ies are begin­ning to assist. Nutritional genomics is a rel­a­tively new field of research that includes nutri­ge­net­ics, nutri-genomics, nutri-metabolomics, and nutri-miRomics. This broad new area of research explores how nutri­ents and dietary pat­terns inter­act with our genome and influ­ence our genetic dis­po­si­tion.

A recent review, pub­lished in Nutrients, 2016, aimed to assess cur­rent knowl­edge on the MedDiet in terms of nutri­tional genomics mech­a­nisms that could help explain the MedDiet’s ben­e­fits in pre­vent­ing car­dio­vas­cu­lar dis­ease (CVD).

Nutrigenetics

Genetic pre­dis­po­si­tion is aris­ing as a pre­dom­i­nant area of nutri­tional research to help iden­tify dif­fer­ent sub­groups that may ben­e­fit from more inten­sive dietary inter­ven­tion. It has been shown that dif­fer­ent geno­types respond to dif­fer­ent dietary pat­terns. Therefore, nutri­ge­net­ics looks at gain­ing a deeper under­stand­ing of the mech­a­nisms asso­ci­ated with indi­vid­ual vari­abil­ity.

For exam­ple, risk fac­tors for CVD asso­ci­ated with genetic pre­dis­po­si­tion include fast­ing glu­cose, total cho­les­terol, LDL cho­les­terol, and triglyc­eride con­cen­tra­tions in some indi­vid­u­als.

Quite incred­i­bly, it has been shown that these genet­i­cally pre­dis­posed traits could be atten­u­ated by adher­ence to the MedDiet. This gene-diet inter­ac­tion was also shown to influ­ence telom­ere length, a bio­marker of bio­log­i­cal aging.

It is now becom­ing appar­ent that healthy dietary pat­terns such as the MedDiet trig­ger var­i­ous responses to genes. The researchers stat­ing, ​“Glycaemia, lipid pro­file, stroke inci­dence, telom­eres length, and emo­tional eat­ing behav­ior are some of the char­ac­ter­is­tics that have been seen to be affected by genetic pre­dis­po­si­tion and adher­ence to the Mediterranean diet.”

Nutrigenomics

This area of research sug­gests that nutri­ents and dietary pat­terns influ­ence direct gene expres­sion or through induc­ing epi­ge­netic mod­i­fi­ca­tions.

It’s sug­gested that the high lev­els of antiox­i­dants in the MedDiet pro­duce its pro­tec­tive action, as antiox­i­dants have been shown to mod­u­late gene expres­sion via down reg­u­lat­ing both oxi­da­tion and inflam­ma­tion. More recently it has also been dis­cov­ered that diet can directly and indi­rectly influ­ence the immune sys­tem.

In rela­tion to CVD, extra vir­gin olive oil (EVOO) has been shown to help mod­u­late ath­er­o­scle­ro­sis, renin-angiotensin, nitric oxide and angiopoi­etin sig­nal­ing.

Nutri-Metabolomics

According to the study, ​“Metabolomics aims to study the entire small mol­e­cule (metabo­lite) com­ple­ment of a system….[In the human body] a huge vari­ety of metabo­lites exist, includ­ing pep­tides, lipids, nucleotides, car­bo­hy­drates, amino acids, and car­bo­hy­drates.”

At this early stage of research, many new nutri­tional dis­cov­er­ies are being made due to metabolomics. For exam­ple, being able to assess dietary pat­terns based on uri­nary metabolome pro­file, test­ing adher­ence to and results of par­tic­u­lar dietary pat­terns, and estab­lish­ing bio­mark­ers that could offer an addi­tional level of nutri­tional per­son­al­iza­tion based on gut micro­biota.

At this stage, there aren’t any defin­i­tive con­clu­sions but from what has been stud­ied, the MedDiet influ­ences all out­comes of metabolomics in a pos­i­tive direc­tion.

Nutri-miRomics

Nutri-miRomics is a sub­set of nutri­tional genomics that looks at microRNAs and their func­tion. According to the study microRNA ​“have emerged as the major reg­u­la­tors of a great num­ber of phys­i­o­log­i­cal processes includ­ing cell dif­fer­en­ti­a­tion, apop­to­sis, and lipid metab­o­lism, and they have been reported to reg­u­late glu­cose home­osta­sis, cell func­tion, and insulin sig­nal­ing.”

One of the major func­tions of microRNAs is to silence their tar­get genes, influ­enc­ing the above-men­tioned reg­u­la­tors and hav­ing out­comes on over­all health and dis­ease. For exam­ple, microRNAs have emerged as epi­ge­netic reg­u­la­tors in CVD.

Nutritional genomics is a rel­a­tively new and com­plex area of research that is also incred­i­bly excit­ing. Being able to study var­i­ous aspects of nutri­tion-related mol­e­c­u­lar mech­a­nisms opens up many pos­si­bil­i­ties for gain­ing knowl­edge and under­stand­ing about human biol­ogy and using dietary inter­ven­tions on a more indi­vid­ual basis. Early evi­dence sug­gests that a MedDiet and EVOO both influ­ence some of these mol­e­c­u­lar mech­a­nisms in a pos­i­tive way.

Being that the MedDiet is one of the most exten­sively stud­ied dietary pat­terns, nutri­tional genomics may even­tu­ally clear up some of the ambi­gu­ity sur­round­ing the asso­ci­a­tions and results found in pre­vi­ous stud­ies.

Certainly, there is still much research to be done but the future of nutri­tional sci­ence looks very excit­ing, with the abil­ity to estab­lish opti­mal ​“doses” of dietary pat­terns based on an indi­vid­u­al’s genetic pre­dis­po­si­tion and other intri­cate fac­tors.

• Nutrients