History of the Human Appetite Research Unit

The Human Appetite Research Unit (known As HARU) was established by John Blundell and became operational in 1990. JB had important support from Peter Rogers, Victoria Burley and Sandra Briggs. However, appetite research with humans had begun much earlier with the first studies carried out in 1975 and the first publication in 1977. The pre-HARU period established methodologies and research platforms that were incorporated into the research practice of HARU from its inception. The first PhD in human appetite research was Andy Hill (1986). The 15 years prior to 1990 were extremely productive and generated a number of fundamental studies on appetite. These included:

• Development of the 4 visual analogue rating scales – hunger, fullness, desire to eat and prospective consumption – (Rogers and Blundell, 1979) which were adopted by the research community and are still being used today.
  One of the first demonstrations of the satiating power of protein over CHO (Hill and Blundell, 1986).
• The first use of temporal tracking of ratings of appetite sensations after a meal to demonstrate the changing intensity of satiety (Hill, Magson and Blundell, 1984).
• The analysis of microstructure of eating to define differences in the actions of anorexic drugs (Rogers and Blundell, 1980). This approach was foreseen in an earlier article in The Lancet on the strategies and tactics of the use of anti-obesity drugs (Blundell, 1976)
• The development of the first craving questionnaire to measure the perceived control of eating (CoEQ) by Hill, Weaver and Blundell, 1991.
• Some of the first studies demonstrating the amplifying effect of high fibre breakfasts on satiety (Burley, Leeds and Blundell, 1986; Blundell and Burley, 1987).
• The initiation of research on functional foods for satiety through the use of proteinase inhibitors to promote the release of CCK (Hill, Peikin, Ryan and Blundell, 1990), and the measurement of plasma amino acids after protein or carbohydrate breakfasts (Teff, Young and Blundell, 1989) to link satiety to brain neurotransmitter action.

The pre-HARU period was also characterised by a series of intensive studies using artificial (high intensity) sweeteners, calorific sweeteners and sweetness inhibitors to uncouple ‘sweetness and energy’ and therefore to demonstrate the separate effects of sweetness and energy on appetite control. (Rogers and Blundell, 1988; Rogers, Carlyle and Blundell, 1989; Blundell, Rogers and Hill, 1989 and several other articles). One particularly influential article published in the Lancet on the ‘paradoxical effects of an intense sweetener’ (Blundell and Hill, 1986) generated intense discussion and media coverage. Using the ‘additive’ and ‘substitutive’ experimental principles (Rogers and Blundell, 1989) the uniquely anorectic action of aspartame (without tasting) was demonstrated (Rogers, Alikhanizadeh and Blundell, 1989) and lead to the submission of a patent with the British Technology Group. These experimental designs were also used with amino acid manipulations including tryptophan, phenylalanine, Tryp-Phe and Asp-Phe; and with drugs including d-amphetamine, dl- fenfluramine (Rogers and Blundell, 1979) and dex-fenfluramine (Blundell and Hill, 1987) which described serotoninergic modulation of meal patterns and alliesthesia (Blundell and Hill, 1988). On the basis of these studies it was proposed that serotonin activation potentiated the satiating capacity of food-induced satiety (Blundell and Hill, 1987).

During this period the research was funded by AFRC, SERC, Department of Health, British Technology Group and Pharma and Food Industry.

Between 1979 and 1990 a total of 61 publications on human appetite were produced including 39 scientific experimental articles. The others were theoretical, conceptual or methodological papers including chapters in books. Among these was the first publication of the ‘Satiety Cascade’ (Blundell, Rogers and Hill, 1987) – a conceptual approach to the measurement of the satiating capacity of foods – which has now been revised, elaborated and extended by JB, David Mela, Jason Halford, Morten Kringelbach, Ray Fuller, Martin Yeomans, Graham Finlayson, and others. There are now several versions of the classic cascade (in seven languages that I am aware of), and it has recently featured on the cover of a book on Satiation and Satiety (Blundell and Bellisle, 2013). The Satiety Cascade identifies the important difference between Satiation and Satiety, a feature which is currently particularly relevant for the characterisation of functional foods for appetite control. During this period the arrival of Victoria Burley from Queen Elizabeth College London was very important in providing nutritional know-how and expertise, and thereby giving credibility to all the studies involving diet formulations and food consumption. Consequently when the HARU was commissioned in 1990 all of the methodological procedures and experimental platforms to support the appetite laboratory were in place and had been validated.

The body of research – funded by research councils, partners in the food and pharma industry and the UK government – carried out and published during the late 1970s and 1980s – persuaded the University that it was worth investing in a Human Appetite Research Facility in Leeds. In 1988 JB wrote the business case for a new Research Facility and, together with Peter Rogers and Victoria Burley designed and costed the building with great technical support from Sandy Briggs. With Tony Chapman’s strong backing the HARU was included in the plans for the East Wing extension of the Psychology Building, and completed in 1990. There was no official opening but research began immediately. Clare Lawton, who was completing a PhD on serotonin and macronutrients in rats (PhD awarded 1991), joined the HARU shortly after it opened and started work with JB on anti-obesity drugs and appetite in humans. The first PhD students all had BSc qualifications in dietetics/nutrition or MSc degrees in Human Nutrition. This was very important in order to provide credibility and expertise for the nutritional component of the behavioural work. The first wave of PhDs were awarded in 1994 – Jackie Smith-Cotton (BSc Dietetics), Sue Green (MSc Human Nutrition) and Neil King (MSc Human Nutrition) – and the next 3 in 1997 – Jennie Macdiarmid (BSc Nutrition) , Alison Greenhough (BSc Pharmacology) and Helen DeLargy (BSc Psychology). At the present time 0ver 40 PhDs (from 6 supervisors or co-supervisors in IPS) have been awarded to students who have carried out their research in the HARU at University of Leeds.

Human Appetite research has been carried out in Leeds University for over 35 years, and the HARU reaches its 25th anniversary in 2015