Today, hormones and taste reveal the secrets of love.

Daisies are a thing of the past. In a new study by ttz Bremerhaven, biochemical analyses and taste tests give an insight into the behaviour of people in love. The research institute is investigating the influence of hormone levels on the taste impressions and consumer behaviour of test candidates.

She loves me, she loves me not…People who have recently fallen in love are in a “state of emergency”. Their bodies release a whole range of molecular messengers which kidnap them to Cloud Nine. ttz Bremerhaven asked itself how these emotional fireworks influence taste and consumer behaviour and whether there is a connection to hormone levels. “The background to our study is the linking of social science methods such as taste sensorics with ‘hard’ biochemical findings”, explains Werner Mlodzianowski, Managing Director of ttz Bremerhaven.

The study has two methodical approaches: On the one hand, the observation of the taste impressions of test candidates together with a questionnaire. On the other hand, hormone tests which were carried out with saliva samples. BIBIS, ttz’s Institute of Biological Information Systems, determined the hormone levels or the biomarkers testosterone and oxytocin on the basis of the participants’ saliva. A total of 46 consumers aged between 20 and 40 years took part in the study, of which 19 were male and 27 were female. Persons who had recently fallen in love were recruited in a selection procedure. Individuals who had been in a relationship for a longer period of time and single people served as control groups.

Long-term couples taste better than people in love and single persons

The results of the taste tests show that the group of people who had recently fallen in love has a rather high salt threshold in comparison to single persons and people who have been in a relationship for a longer period of time (there is a saying that a cook in love adds too much salt to his dishes). What is noticeable is that the men and women who have been in a relationship as a couple for longer easily recognized the basic types of taste, i.e. sweet, sour, bitter and salty. Stable partnerships obviously have a favourable impact on humans’ sense of smell and taste. Other studies emphasize the positive health effects of the lifestyle of married persons in comparison to single people.

Immaterial values are preferred, but for how much?

Following the taste tests, the test candidates reported on their consumer behaviour on Valentine’s Day. All test persons tended rather to decide in favour of a joint experience, such as a visit to a restaurant or the cinema, instead of “classic” Valentine’s Day gifts such as flowers or chocolate. People who had recently fallen in love spend more on average on a Valentine’s Day present for their partner than couples in a long-term relationship. And they believe that their partner would invest the same amount or even more in their Valentine’s Day gift.

Demanding women
The survey on the price of Valentine’s Day presents also revealed that women on average spend less on the gift than men. Conversely however, she expects the man to spend more on her present. The results clearly show that the emotional “state of emergency” of being in love not only influences a person’s sense of taste but also his or her consumer behaviour.

How do hormones influence taste?

Interestingly, the testosterone level in men in love drops whilst in women it is raised. With oxytocin, the so-called “cuddle hormone” it is different: It represents more feminine characteristics, increases affection and is produced in increased levels during childbirth or breast-feeding. In the case of people in love, the oxytocin level is generally raised – in men too. Professor Carsten Harms, Head of BIBIS, comments: “Hormones steer all metabolic pathways in our body and thus also our behaviour. Thus a correlation of those hormones which are released in a state of emergency like love is an important instrument for evaluating the sense of taste.”

Testosterone level is equal in both men and women in love
In the case of the testosterone levels in women, it is noticeable that those who are in a relationship exhibit a lower testosterone value in their saliva than single women and ones who have recently fallen in love. This can be an indication for a peaceful and balanced life. In the case of men in love, the testosterone value sinks significantly in comparison to single men and men in relationships. This corroborates the theory that men in love increase their bonding capacity and appear more likeable to their potential partner through reduced testosterone levels (in conjunction with a raised oxytocin value).

Under “normal” conditions, the testosterone level in men and women is very different. Men have a higher level and women a lower one. In the case of men and women in love however, the testosterone level is more or less the same.

Oxytocin, the “cuddle hormone”, influences the bonding capacity of men
Women fundamentally have a higher oxytocin level in their saliva than men. It is higher amongst women in a relationship than in single women. When a woman is in love, the level increases further. Single men have a very low level of oxytocin in their saliva. Men in relationships have about the same oxytocin level as women in relationships. Science suspects that a higher oxytocin level in particular in men increases the readiness to bond and to care for offspring.

Scientific publication to follow

Through the correlation of the biomarkers with the sensory survey, a reliable interpretation of the taste results could be achieved. The sample and results of the survey drew a picture of the social significance of being in love which, together with the hormone status data, allowed it to be associated to behaviour. First correlations show poorer taste perception amongst persons with higher testosterone levels. Further statements will follow in a scientific paper.

No kissing please! Further information on how the tests were performed

Since messenger substances are transmitted via saliva, kissing before the samples were taken was undesirable. The same applied for sexual intercourse, where large amounts of oxytocin are produced and transmitted. What was also important for correct results was that the test persons did not drink any coffee or eat anything in the hour prior to the start of the test.

A so-called threshold test took place in the cabins of ttz’s sensory laboratory. The test candidates were asked to taste various concentrations of the basic types of taste, i.e. sweet, sour, bitter and salty, and to state from which concentration upwards they could recognize the taste. The saliva samples were subsequently examined in ttz’s Institute of Biological Information Systems (BIBIS).

ttz Bremerhaven is an independent research institute and performs application-related research and development. Under the umbrella of ttz Bremerhaven, an international team of experts is working in the fields of food, environment and health.