What Is Metabolic Syndrome?
Metabolic syndrome is caused by having more than one condition. Metabolic syndrome often leaves individuals with headaches, joint pain, fatigue, and more! Metabolic syndrome is an epidemic all over the world, but in the US, we are seeing this condition all too often.
Metabolic Syndrome can be defined as having two or more of the conditions listed below:
- Women with abdominal fat or a waistline greater than 35
- Men with abdominal fat or a waistline greater than 40
- Individuals with high blood pressure ( 130/85 or higher)
- Patients with triglycerides higher than 150
- A fasting glucose of 100 or greater
- Low HDL ( good cholesterol ) less than 40 in men and 50 for women
These symptoms are often associated with inflammation. Many people believe inflammation is just something that occurs in the joints and on the skin, but inflammation can occur to the organs inside the body and create havoc.
Metabolic syndrome does not target a specific population but can affect anyone who has an overlap of the factors listed above. Those who have an “apple” or “pear” body shape, are likely to have higher abdominal fat, and therefore are more at risk.
As individuals age, their chances of developing metabolic syndrome increases. On top of age, previously having or having a history of diabetes in one’s family also increases their risk of developing metabolic syndrome.
Speaking from personal experience, and having Type 1 Diabetes myself, I can say that metabolic syndrome really takes a toll on one’s body. With experiencing these symptoms first hand, it can leave your body feeling exhausted. When the blood glucose level in the body rises, it causes the blood to become thick due to the excess sugar in the blood. This then causes the heart to work harder and raise the body’s blood pressure due to the effort needed to pump. From here, the body responds with a hard and heavy headache, nausea, occasional vomiting, increased thirst, increased urination, and blurred vision. Recovering from a day of high blood sugars can leave you feeling defeated and similar to feeling like you are recovering from the flu.
One of the things that occur within the body when an individual has metabolic syndrome is their insulin sensitivity decreases. Insulin is the hormone produced that helps to turn the food you eat into fuel for the body or store it as fat. When the insulin sensitivity becomes decreased, it means not enough glucose in the body is being absorbed.� Leading to high blood glucose levels and increases the risk for Type 2 Diabetes.
For those who are suffering from metabolic syndrome, or have one or more of the above risk factors there are ways to take charge. The benefits of taking charge and preventing metabolic syndrome from getting worse or returning means getting back the energy you thought was lost. By decreasing your symptoms and increasing your energy, you could be feeling better than you remembered.
The best diet to quickly gain control of blood sugars and raise HDL is the ketogenic diet. This diet works by eating low carb, high-fat foods. In turn, this makes the body burn fat as fuel rather than carbohydrates. It starts by burning the fat around the pancreas and liver and then starts to burn the intramuscular fat ( excess abdominal weight ). By eliminating most carbs and increasing water intake, individuals can see a decrease in depression, brain fog, their risk of stroke, and blood pressure. All while seeing an increase in sleep and energy.
One of the best ways to reach your goals and stay healthy is to work with a team who understands them and is willing to educate you. We provide 1:1 coaching, scales to track weight that also reports the water weight and BMI of the individual, wrist bands to track caloric activity, and education. The education will help you understand why you are following a specific diet or food guidelines, how that food is breaking down to help you, and what foods to avoid. We will never leave a patient confused or with unanswered questions.
Speaking from personal experience, it is best to get a handle on these symptoms before they cause permanent damage. There are ways and things to do to help reduce your risk. I highly recommend seeing us, or a local doctor to start to build your plan. We can create personalized plans that will help you reach your goals, lower your risk, and work with your lifestyle. Take it from me, you do not want to be stuck feeling the side effects metabolic syndrome comes with.� -Kenna Vaughn, Senior Health Coach
The scope of our information is limited to chiropractic, musculoskeletal, and nervous health issues or functional medicine articles, topics, and discussions. We use functional health protocols to treat injuries or disorders of the musculoskeletal system. Our office has made a reasonable attempt to provide supportive citations and has identified the relevant research study or studies supporting our posts. We also make copies of supporting research studies available to the board and or the public upon request. To further discuss the subject matter above, please feel free to ask Dr. Alex Jimenez or contact us at 915-850-0900.
We usually talk of energy in general terms, as in �I don�t have a lot of energy today� or �You can feel the energy in the room.� But what really is energy? Where do we get the energy to move? How do we use it? How do we get more of it? Ultimately, what controls our movements? The three metabolic energy pathways are the�phosphagen system, glycolysis�and the�aerobic system.�How do they work, and what is their effect?
The energy for all physical activity comes from the conversion of high-energy phosphates (adenosine�triphosphate�ATP) to lower-energy phosphates (adenosine�diphosphate�ADP; adenosine�monophosphate�AMP; and inorganic phosphate, Pi). During this breakdown (hydrolysis) of ATP, which is a water-requiring process, a proton, energy and heat are produced: ATP + H2O ���ADP + Pi�+ H+�+ energy + heat. Since our muscles don�t store much ATP, we must constantly resynthesize it. The hydrolysis and resynthesis of ATP is thus a circular process�ATP is hydrolyzed into ADP and Pi, and then ADP and Pi�combine to resynthesize ATP. Alternatively, two ADP molecules can combine to produce ATP and AMP: ADP + ADP ���ATP + AMP.
During short-term, intense activities, a large amount of power needs to be produced by the muscles, creating a high demand for ATP. The phosphagen system (also called the ATP-CP system) is the quickest way to resynthesize ATP (Robergs & Roberts 1997). Creatine phosphate (CP), which is stored in skeletal muscles, donates a phosphate to ADP to produce ATP: ADP + CP ���ATP + C. No carbohydrate or fat is used in this process; the regeneration of ATP comes solely from stored CP. Since this process does not need oxygen to resynthesize ATP, it is anaerobic, or oxygen-independent. As the fastest way to resynthesize ATP, the phosphagen system is the predominant energy system used for all-out exercise lasting up to about 10 seconds. However, since there is a limited amount of stored CP and ATP in skeletal muscles, fatigue occurs rapidly.
Glycolysis is the predominant energy system used for all-out 
Since humans evolved for aerobic activities (Hochachka, Gunga & Kirsch 1998; Hochachka & Monge 2000), it�s not surprising that the aerobic system, which is dependent on oxygen, is the most complex of the three energy systems. The metabolic reactions that take place in the presence of oxygen are responsible for most of the cellular energy produced by the body. However, aerobic metabolism is the slowest way to resynthesize ATP. Oxygen, as the patriarch of metabolism, knows that it is worth the wait, as it controls the fate of endurance and is the sustenance of life. �I�m oxygen,� it says to the muscle, with more than a hint of superiority. �I can give you a lot of ATP, but you will have to wait for it.�
Fat, which is stored as triglyceride in adipose tissue underneath the skin and within skeletal muscles (called�intramuscular triglyceride), is the other major fuel for the aerobic system, and is the largest store of energy in the body. When using fat, triglycerides are first broken down into free fatty acids and glycerol (a process called�lipolysis). The free fatty acids, which are composed of a long chain of carbon atoms, are transported to the muscle mitochondria, where the carbon atoms are used to produce acetyl-CoA (a process called�beta-oxidation).
It was during the period between 1910 and 1920 when it was suggested for the first time that a cluster of associated metabolic disturbances tended to coexist together [1]. Since then, different health organisms have suggested diverse definitions for metabolic syndrome (MetS) but there has not yet been a well-established consensus. The most common definitions are summarized in Table 1. What is clear for all of these is that the MetS is a clinical entity of substantial heterogeneity, commonly represented by the combination of obesity (especially abdominal obesity), hyperglycemia, dyslipidemia and/or hypertension [2�6].
Several dietary strategies and their potential positive effects on the prevention and treatment of the different metabolic complications associated to the MetS, are described below and summarized in Table 2.
2.1. Energy-Restricted Diet Strategies
The very long-chain eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are essential omega-3 polyunsaturated fatty acids (n-3 PUFAs) for human physiology. Their main dietary sources are fish and algal oils and fatty fish, but they can also be synthesized by humans from ?-linolenic acid [40].
Over the last ten years, the concern about the quality of the carbohydrates (CHO) consumed has risen [46]. In this context, the glycemic index (GI) is used as a CHO quality measure. It consists in a ranking on a scale from 0 to 100 that classifies carbohydrate-containing foods according to the postprandial glucose response [47]. The higher the index, the more promptly the postprandial serum glucose rises and the more rapid the insulin response. A quick insulin response leads to rapid hypoglycemia, which is suggested to be associated with an increment of the feeling of hunger and to a subsequent higher caloric intake [47]. The glycemic load (GL) is equal to the GI multiplied by the number of grams of CHO in a serving [48].
Dietary total antioxidant capacity (TAC) is an indicator of diet quality defined as the sum of antioxidant activities of the pool of antioxidants present in a food [55]. These antioxidants have the capacity to act as scavengers of free radicals and other reactive species produced in the organisms [56]. Taking into account that oxidative stress is one of the remarkable unfortunate physiological states of MetS, dietary antioxidants are of main interest in the prevention and treatment of this multifactorial disorder [57]. Accordingly, it is well-accepted that diets with a high content of spices, herbs, fruits, vegetables, nuts and chocolate, are associated with a decreased risk of oxidative stress-related diseases development [58�60]. Moreover, several studies have analyzed the effects of dietary TAC in individuals suffering from MetS or related diseases [61,62]. In the Tehran Lipid and Glucose Study it was demonstrated that a high TAC has beneficial effects on metabolic disorders and especially prevents weight and abdominal fat gain [61]. In the same line, research conducted in our institutions also evidenced that beneficial effects on body weight, oxidative stress biomarkers and other MetS features were positively related with higher TAC consumption in patients suffering from MetS [63�65].
The macronutrient distribution set in a weight loss dietary plan has commonly been 50%�55% total caloric value from CHO, 15% from proteins and 30% from lipids [57,68]. However, as most people have difficulty in maintaining weight loss achievements over time [69,70], research on increment of protein intake (>20%) at the expense of CHO was carried out [71�77].
The concept of the 
New studies focused on the molecular action of nutritional bioactive compounds with positive effects on MetS are currently an objective of scientific research worldwide with the aim of designing more personalized strategies in the framework of molecular nutrition. Among them, flavonoids and antioxidant vitamins are some of the most studied compounds with different potential benefits such as antioxidant, vasodilatory, anti-atherogenic, antithrombotic, and anti-inflammatory effects [119]. Table 3 summarizes different nutritional bioactive compounds with potential positive effects on MetS, including the possible molecular mechanism of action involved.
Vitamin C, ascorbic acid or ascorbate is an essential nutrient as human beings cannot synthesize it. It is a water-soluble antioxidant mainly found in fruits, especially citrus (lemon, orange), and vegetables (pepper, kale) [120]. Several beneficial effects have been associated to this vitamin such as antioxidant and anti-inflammatory properties and prevention or treatment of CVD and type 2 diabetes [121�123].
Hydroxytyrosol (3,4-dihydroxyphenylethanol) is a phenolic compound mainly found in olives [132].
Quercetin is a predominant flavanol naturally present in vegetables, fruits, green tea or red wine. It is commonly found as glycoside forms, where rutin is the most common and important structure found in nature [141].
Tocopherols, also known as vitamin E, are a family of eight fat-soluble phenolic compounds whose main dietary sources are vegetable oils, nuts and seeds [130,158].
Catechins are polyphenols that can be found in a variety of foods including fruits, vegetables, chocolate, wine, and tea [175]. The epigallocatechin 3-gallate present in tea leaves is the catechin class most studied [176].
PubMed was searched from the earliest possible date to May 2014 to identify review articles that outlined the pathophysiology of MetS and T2DM. This led to further search refinements to identify inflammatory mechanisms that occur in the pancreas, adipose tissue, skeletal muscle, and hypothalamus. Searches were also refined to identify relationships among diet, supplements, and glycemic regulation. Both animal and human studies were reviewed. The selection of specific supplements was based on those that were most commonly used in the clinical setting, namely, gymnema sylvestre, vanadium, chromium and ?-lipoic acid.
Under normal conditions, skeletal muscle, hepatic, and adipose tissues require the action of insulin for cellular glucose entry. Insulin resistance represents an inability of insulin to signal glucose passage into insulin-dependent cells. Although a genetic predisposition can exist, the�etiology of insulin resistance has been linked to chronic low-grade inflammation.1 Combined with insulin resistance-induced hyperglycemia, chronic low-grade inflammation also sustains MetS pathophysiology.1
Caloric excess and a sedentary lifestyle contribute to the accumulation of subcutaneous and visceral adipose tissue. Adipose tissue was once thought of as a metabolically inert passive energy depot. A large body of evidence now demonstrates that excess visceral adipose tissue acts as a driver of chronic low-grade inflammation and insulin resistance.27,34
Eating behavior in the obese and overweight has been popularly attributed to a lack of will power or genetics. However, recent research has demonstrated a link between hypothalamic inflammation and increased body weight.41,41
Feeding generally leads to a short-term increase in both oxidative stress and inflammation. 41 Total�calories consumed, glycemic index, and fatty acid profile of a meal all influence the degree of postprandial inflammation. It is estimated that the average American consumes approximately 20% of calories from refined sugar, 20% from refined grains and flour, 15% to 20% from excessively fatty meat products, and 20% from refined seed/legume oils.45 This pattern of eating contains a macronutrient composition and glycemic index that promote hyperglycemia, hyperlipemia, and an acute postprandial inflammatory response. 46 Collectively referred to as postprandial dysmetabolism, this pro-inflammatory response can sustain levels of chronic low-grade inflammation that leads to excess body fat, coronary heart disease (CHD), insulin resistance, and T2DM.28,29,47
Diagnosis of MetS has been linked to an increased risk of developing T2DM and cardiovascular disease over the following 5 to 10 years. 1 It further increases a patient’s risk of stroke, myocardial infarction, and death from any of the aforementioned conditions.1
Research has identified nutrients that play key roles in promoting proper insulin sensitivity, including vitamin D, magnesium, omega-3 (n-3) fatty acids, curcumin, gymnema, vanadium, chromium, and ?-lipoic acid. It is possible to get adequate vitamin D from sun exposure and adequate amounts of magnesium and omega-3 fatty acids from food. Contrastingly, the therapeutic levels of chromium and ?-lipoic acid that affect insulin sensitivity and reduce�insulin resistance cannot be obtained in food and must be supplemented.
Vitamin D, magnesium, and n-3 fatty acids have multiple functions, and generalized inflammation reduction is a common mechanism of action.74�80 Their supplemental use should be considered in the context of low-grade inflammation reduction and health promotion, rather than as a specific treatment for MetS or T2DM.
Gymnemic acids are the active component of the G sylvestre plant leaves. Gymnemic acids are the active component of the G sylvestre plant leaves. Studies evaluating G sylvestre’s effects on diabetes in humans have generally been of poor methodological quality. Experimental animal studies have found that gymnemic acids may decrease glucose uptake in the small intestine, inhibit gluconeogenesis, and reduce hepatic and skeletal muscle insulin resistance.99 Other animal studies suggest that gymnemic acids may have comparable efficacy in reducing blood sugar levels to the first-generation sulfonylurea, tolbutamide.100
Vanadyl sulfate has been reported to prolong the events of insulin signaling and may actually improve insulin sensitivity.101 Limited data suggest that it inhibits gluconeogenesis, possibly ameliorating hepatic insulin resistance. 100,101 Uncontrolled clinical trials have reported improvements in insulin sensitivity using 50 to 300 mg daily for periods ranging from 3 to 6 weeks. 101�103 Contrastingly, a recent randomized, double-blind, placebo-controlled trial found that 50 mg of vanadyl sulfate twice daily for 4 weeks had no effect in individuals with impaired glucose tolerance. 104 Limited clinical and experimental data exist supporting the use of vanadyl sulfate to improve insulin resistance,�and further research is warranted regarding its safety and efficacy.
Diets high in refined sugar and flour are deficient in chromium (Cr) and lead to an increased urinary excretion of chromium. 105,106 The progression of MetS is not likely caused by a chromium deficiency, 107 and dosages that benefit glycemic regulation are not achievable through food. 106,108,109
Humans derive ?-lipoic acid through dietary means and from endogenous synthesis. 111 The foods richest in ?-lipoic acid are animal tissues with extensive metabolic activity such as animal heart, liver, and kidney, which are not consumed in large amounts in the typical American diet. 111 Supplemental amounts of ?-lipoic acid used in the treatment of T2DM (300-600 mg) are likely to be as much as 1000 times greater than the amounts that could be obtained from the diet.112
This is a narrative overview of the topic of MetS. A systematic review was not performed; therefore, there may be relevant information missing from this review. The contents of this overview focuses on the opinions of the authors, and therefore, others may disagree with our opinions or approaches to management. This overview is limited by the studies that have been published. To date, no studies have been published that identify the effectiveness of a combination of a dietary intervention, such as the Spanish 
Obesity is a complex, multifactorial disease, and better understanding of the mechanisms underlying the interactions between lifestyle, environment, and genetics is critical for developing effective strategies for prevention and treatment [1].
Animal models provide unique opportunities for highly controlled studies that provide mechanistic insight into�the role of specific epigenetic marks, both as indicators of current metabolic status and as predictors of the future risk of obesity and metabolic disease. A particularly important aspect of animal studies is that they allow for the assessment of epigenetic changes within target tissues, including the liver and hypothalamus, which is much more difficult in humans. Moreover, the ability to harvest large quantities of fresh tissue makes it possible to assess multiple chromatin marks as well as DNA methylation. Some of these epigenetic modifications either alone or in combination may be responsive to environmental programming. In animal models, it is also possible to study multiple generations of offspring and thus enable differentiation between trans-generational and intergenerational transmission of obesity risk mediated by epigenetic memory of parental nutritional status, which cannot be easily distinguished in human studies. We use the former term for meiotic transmission of risk in the absence of continued exposure while the latter primarily entails direct transmission of risk through metabolic reprogramming of the fetus or gametes.
(i) Epigenetic Changes In Offspring Associated With Maternal Nutrition During Gestation
Maternal nutritional supplementation, undernutrition, and over nutrition during pregnancy can alter fat deposition and energy homeostasis in offspring [11, 13�15, 19]. Associated with these effects in the offspring are changes in DNA methylation, histone post-translational modifications, and gene expression for several target genes,�especially genes regulating fatty acid metabolism and insulin signaling [16, 17, 20�30]. The diversity of animal models used in these studies and the common metabolic pathways impacted suggest an evolutionarily conserved adaptive response mediated by epigenetic modification. However, few of the specific identified genes and epigenetic changes have been cross-validated in related studies, and large-scale genome-wide investigations have typically not been applied. A major hindrance to comparison of these studies is the different develop mental windows subjected to nutritional challenge, which may cause considerably different outcomes. Proof that the epigenetic changes are causal rather than being associated with offspring phenotypic changes is also required. This will necessitate the identification of a parental nutritionally induced epigenetic �memory� response that precedes development of the altered phenotype in offspring.
Emerging studies have demonstrated that paternal plane of nutrition can impact offspring fat deposition and epigenetic marks [31�34]. One recent investigation using mice has demonstrated that paternal pre-diabetes leads to increased susceptibility to diabetes in F1 offspring with associated changes in pancreatic gene expression and DNA methylation linked to insulin signaling [35]. Importantly, there was an overlap of these epigenetic changes in pancreatic islets and sperm suggesting germ line inheritance. However, most of these studies, although intriguing in their implications, are limited in the genomic scale of investigation and frequently show weak and somewhat transient epigenetic alterations associated with mild metabolic phenotypes in offspring.
Stable transmission of epigenetic information across multiple generations is well described in plant systems and C. elegans, but its significance in mammals is still much debated [36, 37]. An epigenetic basis for grand- parental transmission of phenotypes in response to dietary exposures has been well established, including in livestock species [31]. The most influential studies demonstrating effects of epigenetic transmission impacting offspring phenotype have used the example of the viable yellow agouti (Avy) mouse [38]. In this mouse, an insertion of a retrotransposon upstream of the agouti gene causes its constitutive expression and consequent yellow coat color and adult onset obesity. Maternal transmission through the germ line results in DNA methylation�mediated silencing of agouti expression resulting in wild-type coat color and lean phenotype of the offspring [39, 40]. Importantly, subsequent studies in these mice demonstrated that maternal exposure to methyl donors causes a shift in coat color [41]. One study has reported transmission of a phenotype to the F3 generation and alterations in expression of large number of genes in response to protein restriction in F0 [42]; however, alterations in expression were highly variable and a direct link to epigenetic changes was not identified in this system.
While many studies have identified diet-associated epigenetic changes in animal models using candidate site-specific regions, there have been few genome-wide analyses undertaken. A recent study focussed on determining the direct epigenetic impact of high-fat diets/ diet-induced obesity in adult mice using genome-wide gene expression and DNA methylation analyses [43]. This study identified 232 differentially methylated regions (DMRs) in adipocytes from control and high-fat fed mice. Importantly, the corresponding human regions for the murine DMRs were also differentially methylated in adipose tissue from a population of obese and lean humans, thereby highlighting the remarkable evolutionary conservation of these regions. This result emphasizes the likely importance of the identified DMRs in regulating energy homeostasis in mammals.
(i) Genetic association studies. Genetic polymorphisms that are associated with an increased risk of developing particular conditions are a priori linked to the causative genes. The presence of differential�methylation in such regions infers functional relevance of these epigenetic changes in controlling expression of the proximal gene(s). There are strong cis-acting genetic effects underpinning much epigenetic variation [7, 45], and in population-based studies, methods that use genetic surrogates to infer a causal or mediating role of epigenome differences have been applied [7, 46�48]. The use of familial genetic information can also lead to the identification of potentially causative candidate regions showing phenotype-related differential methylation [49].
From these studies, altered methylation of PGC1A, HIF3A, ABCG1, and CPT1A and the previously described RXRA [18] have emerged as biomarkers associated with, or perhaps predictive of, metabolic health that are also plausible candidates for a role in development of metabolic disease.
Epigenetic variation is highly influenced by the underlying genetic variation, with genotype estimated to explain ~20�40 % of the variation [6, 8]. Recently, a number of studies have begun to integrate methylome and genotype data to identify methylation quantitative trait loci (meQTL) associated with disease phenotypes. For instance, in adipose tissue, an meQTL overlapping�with a BMI genetic risk locus has been identified in an enhancer element upstream of ADCY3 [8]. Other studies have also identified overlaps between known obesity and T2DM risk loci and DMRs associated with obesity and T2DM [43, 48, 62]. Methylation of a number of such DMRs was also modulated by high-fat feeding in mice [43] and weight loss in humans [64]. These results identify an intriguing link between genetic variations linked with disease susceptibility and their association with regions of the genome that undergo epigenetic modifications in response to nutritional challenges, implying a causal relationship. The close connection between genetic and epigenetic variation may signify their essential roles in generating individual variation [65, 66]. However, while these findings suggest that DNA methylation may be a mediator of genetic effects, it is also important to consider that both genetic and epigenetic processes could act independently on the same genes. Twin studies [8, 63, 67] can provide important insights and indicate that inter-individual differences in levels of DNA methylation arise predominantly from non-shared environment and stochastic influences, minimally from shared environmental effects, but also with a significant impact of genetic variation.
Prenatal environment: Two recently published studies made use of human populations that experienced �natural� variations in nutrient supply to study the impact of maternal nutrition before or during pregnancy on DNA methylation in the offspring [68, 69]. The first study used a Gambian mother-child cohort to show that both seasonal variations in maternal methyl donor intake during pregnancy and maternal pre-pregnancy BMI were associated with altered methylation in the infants [69]. The second study utilized adult offspring from the Dutch Hunger Winter cohort to investigate the effect of prenatal exposure to an acute period of severe maternal undernutrition on DNA methylation of genes involved in growth and metabolism in adulthood [68]. The results highlighted the importance of the timing of the exposure in its impact on the epigenome, since significant epigenetic effects were only identified in individuals exposed to famine during early gestation. Importantly, the epigenetic changes occurred in conjunction with increased BMI; however, it was not possible to establish in this study whether these changes were present earlier in life or a consequence of the higher BMI.
Postnatal environment: The epigenome is established de novo during embryonic development, and therefore, the prenatal environment most likely has the most significant impact on the epigenome. However, it is now clear that changes do occur in the �mature� epigenome under the influence of a range of conditions, including aging, exposure to toxins, and dietary alterations. For example, changes in DNA methylation in numerous genes in skeletal muscle and PGC1A in adipose tissue have been demonstrated in response to a high-fat diet [75, 76]. Interventions to lose body fat mass have also been associated with changes in DNA methylation. Studies have reported that the DNA methylation profiles of adipose tissue [43, 64], peripheral blood mononuclear cells [77], and muscle tissue [78] in formerly obese patients become more similar to the profiles of lean subjects following weight loss. Weight loss surgery also partially reversed non-alcoholic fatty liver disease-associated methylation changes in liver [79] and in another study led to hypomethylation of multiple obesity candidate genes, with more pronounced effects in subcutaneous compared to omental (visceral) fat [64]. Accumulating evidence suggests that exercise interventions can also influence DNA methylation. Most of these studies have been conducted in lean individuals [80�82], but one exercise study in obese T2DM subjects also demonstrated changes in DNA methylation, including in genes involved in fatty acid and glucose transport [83]. Epigenetic changes also occur with aging, and recent data suggest a role of obesity in augmenting them [9, 84, 85]. Obesity accelerated the epigenetic age of liver tissue, but in contrast to the findings described above, this effect was not reversible after weight loss [84].
DNA methylation changes associated with obesity or induced by diet or lifestyle interventions and weight loss are generally modest (<15 %), although this varies depending on the phenotype and tissue studied. For instance, changes greater than 20 % have been reported in adipose tissue after weight loss [64] and associations between HIF3A methylation and BMI in adipose tissue were more pronounced than in blood [52].
Conclusions
