TiFN PhD fellow Lieke Gijsbers: “From volunteer to friend”

14 October 2017 – During her TiFN PhD research, Lieke Gijsbers organized a 13-week controlled-intervention study with nearly 40 volunteers. The trial provided valuable insights into the vascular effects of sodium and potassium intake, and, in a surprising way, enlarged her network. Gijsbers defended her thesis 13 September 2017 at Wageningen University.

Such an extensive trial is unique in nutrition sciences, says Gijsbers, who was supervised by Dr Marianne Geleijnse from the Human Nutrition department. “Every day, for 13 weeks, volunteers visited the university, were served a hot meal and took a bag of food products home as part of their prescribed menu.”

It was an intense time, for the volunteers and for Gijsbers and her team. “We had many tasks: develop menus; prepare meals; give instructions and regularly measure blood pressure, vascular stiffness, vasodilation, heart rate and renal function”, she illustrates.  

Great commitment
Recruiting 40 volunteers was also quite a job. “Participation in such a long study requires a substantial commitment”, says the nutritionist. Moreover, admission criteria were strict: participants should have slightly-high blood pressure but not be using blood pressure-lowering medicines. “We had to be very creative to find the people we needed; at one local market we offered people free blood-pressure measurement.”

It was worth the effort, says the PhD fellow: “Our study highlighted the importance of sodium reduction in the diet. We also demonstrated that extra potassium helps reducing blood pressure, even in people consuming recommended levels of salt. Substituting potassium for sodium in food products could be a valuable approach.” Currently, the majority of Western people consume far too much table salt: average intake is 9-12 grams per day while the recommended intake is 5-6 grams.

In addition to the scientific insights gained, Gijsbers’ study was personally valuable: “We developed such a nice bond with the volunteers, that we organized a reunion – without the blood tests! – approximately one year after the trial, when all data was analysed and results were available”, she says.

Personal development
Working as a PhD with TiFN was, for Gijsbers, a prerequisite for her professional development: “Just working with so many disciplines opens your eyes and your brain.” She also enjoyed TiFN’s renowned close collaboration with industry. “Our partners were very interested in the work and wanted real detail on the what, how and why of our research. They also came up with interesting ideas, for example for additional lab analyses.”

Gijsbers uses her skills every day in her new job as a clinical programmer at OCS Life Sciences. “Our clients are as involved as TiFN’s industry partners.”

To read more about Gijsbers’ research, click here.

Female doctor checking blood pressure of a patient in the hospital