Thinking of one’s favorite food makes one’s mouth water. But why do we like certain foods so much? London scientists have now investigated whether genes are involved.
Probably everyone has a favorite food item, pasta, steak, or cheese! But why does a meat dish make one person’s mouth water, but another responds to cheese or fish? Why do we like what we like? These questions far exceed the edge of one’s own plate and lead to a laboratory right away. In this case, to London.
Scientists from King’s College, London, have found that specifically distinct tastes, such as spicy, sour, and sweet, are co-determined genetically. But that was not the only finding that was observed. Some food preferences can be traced back to the blood.
Preferences for specific foods and tastes start quite early in human development, ever prior to birth. What people like and dislike, however, changes throughout life into adulthood. While hunger may be among the strongest drives to eat, the decision for or against a dish is determined by many more factors than its nutritional value. The taste, for instance, texture, sight, smell, and also memories and habits rule what we prefer and avoid. And biology, the genetic makeup. The size of this influence has now been investigated by scientists, led by Tess Pallister (1).
More than 2,000 people were included in their study, about half of them twins. All participants filled out online questionnaires of their food preferences. A total of 87 food items and drinks were rated, as well as 18 bodily activities. In addition, scientists drew blood from their volunteers for laboratory tests, searching for a total of 280 substrates. These included carbohydrates, vitamins, amino-acids, fats, peptides, and other chemicals. They then explored whether there were associations between all these information — and there were.
Those that scored fruits and vegetables with high points were more likely to enjoy physical activities and abstain from smoking. Those that preferred distinct tastes, such as olives, garlic, blue cheese, and chili, smoked frequently but also preferred exercises. High scores for sugar and sweets were more frequently associated with a higher body-mass index (BMI) and low preference for physical activities. The same was true for those with a preference for meat.
Following this, the authors wanted to know whether and what role genes and genetic makeup of humans play for these different preferences. For this, they compared identical (mono-zygotic) twins with non-identical (dizygotic) twins that share about half of their genes. Thereby, the scientists could show that specific preferences for strong and distinct tastes, such as sweet, sour, or spicy, are inherited. They claim that they are the first that could demonstrate inheritance of the preference for meat in adults, published in the medical journal Twin Research and Human Genetics. For this, different genes seem to be responsible, and their effects are additive. In fact, other research groups have already identified single gene sections that are associated with a preference for specific foods. A variant of the gene OR6A2, for instance, appears to be responsible for the fact that cilantro tastes like soap only for some people (2)
But Pallister and colleagues did not only want to know what influence genes have on the indulgence for specific foods and meals of their volunteers. They also explored whether the group’s preferences were also mirrored in their blood levels. Again they discovered news.
Those that like sugar and meals with plenty of carbohydrates, such as pasta, lacked predominant metabolites found in fish. The association was specifically strong for a fatty acid named CMPF (3-Carboxy-4-Methyl-5-Propyl-2-Furanopropanoic Acid); low CMPF was associated with specifically low fish and seafood consumption. Meat enthusiasts most frequently exhibited amino acids that also are present in meat or their metabolic products such as creatine.
Among the subjects that scored fruits and vegetables specifically high, the scientists could not identify specific associations with metabolic products in the bloodstream; certain metabolites were only found in the blood of people with very distinct and pronounced taste preferences. In addition, most volunteers were females, so it still needs to be shown whether the results would look different in men.
This is part 13 of a series covering twin health provided by Paul Enck from the Tübingen University Hospital and science writer Nicole Simon. Further studies in twin research can be found at TwinHealth website.
- Pallister T, Sharafi M, Lachance G, Pirastu N, Mohney RP, MacGregor A, Feskens EJ, Duffy V, Spector TD, Menni C. Food Preference Patterns in a UK Twin Cohort. Twin Res Hum Genet. 2015 Dec;18(6):793-805.
- Eriksson N, Wu S, Do CB, Kiefer AK, Tung JT, Mountain JL, Hinds DA, Francke U.A genetic variant near olfactory receptor genes influences cilantro preference. Flavour 2012;1:22