Nutrigenomics or nutrigenetics – the science about nutrition personalized to your genetic profile
The branch of science which studies the relationship between nutrition and genetics is known as nutritional genomics, or nutrigenomics. It tries to explain what effect some nutrients have on a person and helps understand which foods to choose for a long, healthy and vital life. By taking this approach we can achieve optimum nutrition and satisfy the individual needs of each one of us.
All humans are more than 99.9% genetically identical. Changes in the inherited genetic variants may occur in the remaining 0.1%. These are changes in the sequence of nucleotides, the “letters” that make up our genetic code; we call them genetic polymorphisms or natural variations in our genes. These can cause differences in the character or amount of protein encoded by a given gene.
DNA testing services LifeGenetics are focus mainly on those genetic variants (polymorphisms or SNP’s), which were found in research to have a significant impact on the body’s metabolic pathways, meaning that they participate in the absorption and metabolism of nutrients, detoxifying mechanisms, the functioning of muscles and a tendency toward some modern diseases, such as cardiovascular disease and type II diabetes – NUTRIGENOMICS.
This means that some people metabolize certain substances or nutrients (caffeine, nicotine, calcium, vitamin B …) poorly and so it is necessary to take some measures. If we know our genetic peculiarities we can turn them to our advantage through a healthier diet and lifestyle and thus prevent the development of some diseases.
NUTRIGENOMICS, NUTRIGENETICS AND NUTRIGENOMIC PROFILE as well as other derived expressions are regularly misused by various providers. We advise caution when ordering a nutrigenomic analysis – check if the provider truly completes a genetic analysis when claiming that his service is a nutrigenomic or nutrigenetic analysis and not a just “blood-type-diet”. A big fraud indicator is the requirement of your blood sample. A genetic analysis only requires a sample of your saliva or buccal swab. For more information, check the Choosing the DNA test guide >>
A thorough look into the science behind nutrigenomic DNA testing performed by LifeGenetics
Findings that are related to your gene variants are based on the most reliable and cutting-edge research in the field of genetics which have been published in prestigious international scientific journals. The laboratory analyses also follow global trends since they are made using advanced modern technologies.
LifeGenetics recommendations are therefore based on scientific evidence and are presented in seven key areas of health with a detailed scientific explanation:
Cardiovascular system – genes associated with blood plasma homocysteine
This chapter treats the investigation of genes involved in metabolic pathways during the remethylation of homocysteine to cysteine. Homocysteine is sometimes included among the major risk factors for the development of cardiovascular disease, so it is important to determine its potential to accumulate at the genetic level. With the intake of vitamin B6, B12 and folic acid we affect the rate of at which homocysteine converts to cysteine, because these micronutrients have a key role in the metabolic pathways involving homocysteine.
In this chapter we also analyze versions of genes that help determine risk factors for cardiovascular disease; we can use this data to prepare appropriate measures that can prevent or at least delay the onset of disease.
Elevated levels of homocysteine in the blood may be a potential risk factor for other cardiovascular diseases such as stroke, a predisposition to thrombosis, and other conditions. The reason for an elevated homocysteine level in the blood may be inadequate nutrition or genetic variants that reduce the activity of enzymes necessary to remove homocysteine efficiently from your blood. Help lower homocysteine levels by eating the right foods and/or taking dietary supplements containing vitamins B12, B6 and folic acid.
In relation to homocysteine and the cardiovascular system, LifeGenetics Premium analyzes several genes, including the gene for the methylene tetrahydrofolatereductase enzyme (MTHFR). The MTHFR enzyme is involved in the conversion of the amino acid homocysteine to another amino acid, methionine. The two most common and well-known polymorphisms of the gene which encodes it are known to decrease the activity of MTHFR. The best-known and most extensively investigated is the first polymorphism, where in a specific location of the gene a C allele appears in place of a T allele, which affects enzyme activity. Laboratory experiments have shown that the TT genotype of the genetic polymorphism retains only 30% activity compared to the CC genotype and 60% compared to the CT genotype. The reduction of enzyme activity can lead to elevated levels of homocysteine in the blood, especially with low folic acid intake. The frequency of the polymorphic allele (T) in the Slovenian population is between 32 and 36 percent. This polymorphism is more frequent in the Slovenian compared to, for example, the German population (the T-allele frequency in Germans is 25%) and less frequent than in the Italian population (the T-allele frequency in Italians is 44%).
Fats and sugars – Genes associated with glucose metabolism and insulin regulation
Fat metabolism is a very complex process, involving more than 100 genes. In this chapter, we try to determine how an individual metabolizes some types of fatty acids, how fats are stored in the body, released, etc. A more appropriate diet and adequate physical exercise can help reduce body fat percentage and contribute to better health.
Many genes are involved in the regulation of insulin secretion and action, and the glucose metabolic process. Versions of specific genes have a direct impact on these processes, and since humans have different genes, we are also susceptible to differing extents to developing a disease such as diabetes.
Diabetes mellitus, commonly referred to as diabetes, develops when the body does not produce any insulin or produces too little insulin to regulate the blood glucose level (blood sugar); it can also occur because the insulin that is produced has a reduced effect (insulin resistance). Insulin is a hormone produced in the pancreas and responsible for opening the glucose channels that allow the glucose and fatty acids to transfer from the blood to the cells where glucose metabolism takes place. If there is little or no insulin at all or the insulin produced is less efficient, glucose cannot enter the tissues and organs but circulates in the bloodstream, which exerts adverse effects on the body.
Telltale signs of diabetes are thirst and frequent urination, weight loss and frequent infections. If the disease is not treated properly, it can cause serious problems, such as kidney failure, eye damage, nerve damage and blood vessel diseases. Heredity and environmental factors, particularly poor nutrition and lack of physical activity, can lead to the onset of diabetes.
There are several types of diabetes:
- Type I diabetes or insulin-dependent diabetes most often occurs in childhood. This type of diabetes is not curable, but can be managed with medications that help control insulin levels and, consequently, blood sugar levels.
- Type II diabetes or non-insulin-dependent diabetes usually develops later in life, mainly in adults who are overweight and above 40 years of age. This type of diabetes is managed with a healthy diet, weight control and physical activity, and, at advanced stages, with medication.
- Insulin resistance, decreased insulin response or a decreased effect of insulin occurs particularly in obese people. Although the mechanism of insulin resistance has not been fully elucidated, the reasons could be overly large meals and inappropriate nutritional composition, physical inactivity and genetic predisposition.
- The secondary type of diabetes or secondary diabetes can develop as a result of certain medical conditions, such as pancreatic disease, hormonal disorders, the use of certain medications or chemicals, changes in the receptors through which insulin exerts its actions, genetic disorders …
In the chapter on Fats and sugars, in the section on genes associated with glucose metabolism and insulin regulation, we discuss genes which play a role in the development of type 2 diabetes.
Extensive research has shown that the TCF7L2 gene exhibits the strongest association to type 2 diabetes observed to date. TCF7L2 gene polymorphisms (a point mutation where at a specific place inside a gene, a nucleotide C changes into nucleotide T) have been shown to be associated with type II diabetes and low insulin secretion after ingestion of glucose. Because of their predisposition to type II diabetes, people with the TT genotype must pay more attention to their diet and follow healthy lifestyle recommendations.
Food allergies and intolerances – lactose intolerance – Investigation of genes involved in lactose metabolism (milk sugar)in intolerance
In this section, we identify variants of genes involved in lactose metabolism and can thus determine whether or not your body is able to digest lactose.
Consumption of milk and other dairy products is highly recommended since they are an important source of calcium and vitamin D, which are needed for proper growth and bone development. However, in some people consumption of milk can cause unpleasant indigestion. These people may have problems after drinking a single glass of milk; however, the cause lies in their inability to break down milk sugar – lactose. The problem arises because in some children over five years of age the production of lactase, the enzyme that digests lactose, gradually decreases, and so many individuals cannot successfully metabolize milk and dairy products. This phenomenon is called lactose intolerance.
What is actually going on in the body with lactose intolerance?
Normally, lactose is broken down in the small intestine.If there is insufficient lactase in the body, lactose cannot be digested. Lactose does not break down in the small intestine and passes undigested into the large intestine, where it causes digestive problems in two ways: because of its osmotic effect it causes water and electrolyte retention in the colon, and, in addition, it is digested in the large intestine by bacteria that make up our gut flora, producing gases and other by-products of the digestion process. This can lead to some extremely unpleasant gastrointestinal disorders (abdominal pain, diarrhea, flatulence…).
Lactose intolerance is actually a normal human condition and occurs in all mammals in the animal kingdom; lactase is turned off in adult mammals, since it is no longer necessary. Humans are the only mammals that still drink milk after the natural weaning age. We have adapted to drinking milk by having partially or wholly retained the ability to break down lactose. The incidence of lactose intolerance in people from Africa, Asia, Middle East and some Mediterranean countries stands at about 70 percent, compared to only between 5 to 15 percent of people of Northern European and Scandinavian descent.
Less than ten years ago, scientists identified a genetic polymorphism with the help of which it is possible to reliably predict whether an adult’s body can metabolize lactose or not. It is a matter of C changing into T in the intron region of the MCM6 gene. The MCM6 gene affects the functioning of the gene that encodes an enzyme called lactase, and may in the presence of this genetic polymorphism prevent the formation of this enzyme. The C allele is associated with low and T allele with high lactase activity in adulthood. After age five, people with the CC genotype can no longer digest lactose sugar normally and are therefore lactose intolerant. People with the TT or TC genotypes can usually digest lactose normally and we say that they are lactose persistent (or lactose tolerant).
Substances and dependence – genes associated with caffeine metabolism
People with different gene variants digest caffeine differently. For people who metabolize caffeine more slowly, drinking caffeinated beverages may increase the risk of heart attack. The opposite is true for people with a fast metabolism. In this chapter, we analyze a person’s ability to metabolize caffeine, alcohol and nicotine.
Different people respond to caffeine in many different ways: while for some people a single cup of coffee in enough to last a day, others can consume a few in a short period of time and not feel any significant effect. This difference can be partially attributed to a tolerance to caffeine, obtained from a frequent consumption of caffeinated beverages; some differences, however, must be attributed to genetic differences between individuals.
Liver enzymes and variants of the genes encoding these enzymes determine how long it takes us to break down the caffeine. Studies have shown that if people whose bodies break down caffeine slowly drink 2 to 3 cups of coffee a day, their risk of heart attack increases significantly. On the other hand, the findings of some studies suggest that people who are fast metabolizers are at a reduced risk of a heart attack.
The CYP1A2 gene encodes one of the enzymes belonging to the cytochrome P450 family. This enzyme is involved in the first stage of caffeine metabolism. It is known that the half-life of caffeine (the time it takes for half of it to be broken down) in the human body varies between 1.5 and 9.5 hours. This enzyme and the genetic variants that encode it play an important role in speeding up the breakdown of caffeine.
People with the AA genotype are fast caffeine metabolizers and drinking caffeinated beverages does not increase their risk of a heart attack; the opposite is true for people carrying the C allele.
Bones – genes involved in vitamin D metabolism
Osteoporosis and other bone diseases are a complex phenomenon where genetic information is intertwined with environmental influences. In this chapter, we aim to identify some gene variations that have a greater influence on the development of bone problems. We can then make recommendations which may reduce or eliminate these problems.
Bones work with muscles to provide structural support, shape the body and protect internal organs, while bone marrow actively produces blood cells. Almost all of the calcium in the body is stored in bones. Foods rich in calcium and vitamin D help ensure optimal peak bone mass. Hence, if too little calcium is supplied in the diet, the body will take the calcium it needs from the bones. The body will absorb more calcium when there are adequate amounts of protein, magnesium and vitamins D. With the presence of vitamin D, the efficiency of calcium absorption is two to three times higher. Vitamin D is a fat-soluble vitamin that is found, for example, in foods such as oily fish and dairy products, and is also produced by our skin in response to exposure to ultraviolet radiation.
The critical years for building bone mass last until around age 20 and subsequently there are no significant changes in bone density. Adolescents and young adults, whose bones are growing very fast, need more calcium. The latter continues to play an important role through our mature years, when it affects the maintenance of bone mass, and thus reduces the risk of osteoporosis, especially in postmenopausal women whose bone mass has begun to decline. Brittle bones are the result of diseases, among which osteoporosis is the best known. Osteoporosis, or porous bone, is a condition characterized by the loss of bone mass. Bones become brittle and weak and fractures can occur even with small amounts of stress, usually in the spine, hip and wrist. Although osteoporosis mainly affects women, we must not forget that many men are also affected.
In the chapter entitled ‘bones’ we use the LifeGenetics Premium test to analyze genetic polymorphisms (variations) in genes that are in some way associated with bone metabolism. Based on the results of genetic analysis we aim to identify whether a person carries certain versions of genes that could cause problems related to bone metabolism and thus significantly contribute to a reduction in bone mass, and to predict a person’s dietary requirements for calcium and vitamin D. Research has shown that poor nutrition and lifestyle increase the risk of bone problems in people carrying specific gene variants. By taking into account good diet and lifestyle recommendations, you can improve your bone health at any stage in your life, although the effects on bone are most striking in young people up to the age of 30.
In the ‘Bones’ chapter of the LifeGenetics Premium test, we also analyze the gene that encodes one of the collagen molecules, namely an alpha 1 chain of type 1 collagen. Collagen is a binding protein that is an integral part of bone. Therefore, the gene variants studied, in addition to other genetic and environmental factors, play an important role in determining the risk of various bone disorders. This is a genetic polymorphism, where at a specific location of a gene, a T nucleotide replaces a G nucleotide. Research has shown that the T allele is associated with lower bone mineral density (almost 35% of Slovenes carrying T allele have already taken the LifeGenetics genetic test). In subjects with the TT genotype (approx. 4% of our testees carry this genotype) the risk of developing osteoporosis is usually greater than in those with the GG and GT genotypes.
Muscles – genes associated with muscle metabolism and muscle potential
Humans are born with different levels of muscular strength and endurance. We can further exploit this potential through exercise. In this chapter, we aim in particular to determine the difference between aerobic and anaerobic muscular efficiency and prepare appropriate physical activity recommendations. In addition, we also investigate the risk of muscle cramps due to a genetic predisposition.
Muscular capacity depends on many factors, some of which are also genetic. Genes are largely responsible for population differences in the ability to supply oxygen to the muscles, heart muscle performance and muscle fiber composition.
As an example, consider the ACTN3 gene, which can be completely disabled by a single change in the gene. The ACTN3 gene is expressed only in fast-twitch muscle fibers and encodes the protein alpha-actinin-3, which is responsible for stabilizing muscle actin filaments. Point mutation in this gene, which is very common in the global population (the frequency of the mutant allele is between 20 and 50% of the world’s population), results in this protein not being expressed and therefore not being present in the muscles. No disease is associated with this genetic variant, but it is important for muscle performance. The CC genotype represents the active form of this gene and indicates that people who have this genotype are better suited for sprinting. The TT genotype puts more emphasis on other proteins involved in muscular capacity; hence the people with this genotype are better suited for long distance running.
Aerobic or anaerobic exercise? The answer is in the genes!
Around 20% of the population does not get any significant aerobic fitness benefit from regular exercise, according to an international study led by scientists at the University of London. Millions of people who strive to keep fit by jogging, swimming or going to the gym are wasting their time, scientists said. Researchers have discovered that the health benefits of aerobic exercise are determined by our genes.
For these people, regular aerobic exercise will do little to ward off conditions like heart disease and diabetes which aerobic exercise is generally thought to resist.
More than 500 participants in Europe and the US were asked to undergo various aerobic training programs in line with government advice to do 30 minutes of exercise five times a week. By the end of the 20 week program, the majority of people had shown a measurable improvement in how much oxygen their body consumes during exercise, a key indicator of aerobic fitness.
But 20% saw their maximum oxygen increase by less than 5% – a negligible improvement. Around 30% showed no increase in insulin sensitivity, meaning that the exercise did not reduce their risk of diabetes.
A pioneering analysis of muscle tissue samples taken from the participants revealed a set of about 30 genes that predicted the increase in oxygen intake. Of these, 11 were shown to have a particular impact on how much a person could benefit from aerobic exercise.
Selecting an appropriate type of exercise is not only important for maximizing the efficiency of your athletic potential, but also for developing and maintaining vitality and a healthy lifestyle, as well as preventing certain diseases. The LifeGenetics Premium analysis will answer your questions with regard to the type of exercise that best suits your particular genetic profile.
Detoxification – the investigation of genes associated with the genetic material health and body detoxification
People react differently to pesticides, exhaust gases, industrial waste, cigarette smoke and other similar substances. In this chapter we aim to determine how some poisons affect our body, what are the recommended measures and which poisons we should particularly avoid.
We are exposed to poisons and harmful substances to a greater extent than we are aware. Chemicals, cigarette smoke, industrial pollution, pesticide residues on fruits and vegetables, chemical substances in medicinal products and certain food additives are just some of the many harmful substances from the environment to which we are exposed daily and which may adversely affect our health. The human organism is constantly engaged in fighting off these substances and this is how the body detoxifies itself. Repair and detoxification mechanisms at the cellular lever prevent the onset of diseases and numerous other health problems. Gene variants discussed in this chapter are important because they can often determine how the body will fight off harmful substances. In people whose repair mechanisms are less efficient, there are a number of other ways in which the body can defend itself against toxins. The best defense against toxins is a healthy balanced diet.
The SOD2 gene encodes the enzyme that protects the body against damage caused by free radicals. This LifeGenetics test involves an analysis of the SOD2 gene polymorphism, where a C nucleotide changes into a T nucleotide. In people who carry two T- alleles (TT genotype), part of the structure of the enzyme is destroyed, thus reducing the enzyme activity by 30 to 40 percent. If we take into account the findings emerging from various studies, those people who carry the TT genotype should consume larger quantities of antioxidants in order to successfully fight free radicals. This genetic polymorphism is also associated with other areas of health. A study carried out in Slovenia on patients with type 2 diabetes has shown that the TT genotype is associated with a higher risk of coronary and carotid atherosclerosis and other diabetic microvascular complications. This genotype is also associated with higher levels of LDL (“bad”) cholesterol.
Gene based weight loss gives 2-3 times better results
Research conducted at the world-renowned Stanford University, USA, has shown that we can lose 2-3 times more weight with a gene-based diet compared to a traditional diet.
The study involved 101 women. Few undertook a diet based on genetic analysis and the rest based on traditional approaches. Scientists found more progress in women who followed the instructions of their genes, and their diet was 2-3 times more effective.
Women who participated in the study were assigned to four different diets over a one year period: very low-carbohydrate, low-carbohydrate/high-protein, low-fat and very-low-fat diets. Subsequently, a genetic analysis was conducted and the women were divided into three groups according to genotype (low carbohydrate diet responsive genotype (45%), low fat diet responsive genotype (39%) and balanced diet responsive genotype). The study found that those on a diet which matched their genotype lost 2-3 times more weight over 12 months compared with those on the “wrong” diet.
Similar results were also obtained in a Greek study
Greek researchers also spent a year monitoring people who have had a lot of difficulty losing weight in the past; half of them had a menu prepared on the basis of their genetic test results, while the other half consumed a standard hospital diet. They found that people who eat according to their genetic code are more successful at maintaining weight loss compared to people whose diets are based on classic clinical menus.
What about our clients?
We receive many positive reports of weight-loss successes from our customers. On average our clients lose 1 to 1,5 pounds per week! Read what they have to say about the LifeGenetics method >>