Obesity is a vexing issue that continues to pressurize state authorities and health organisations into finding solutions to lift people out of dangerous Body Mass Index (BMI) ranges. More than 1.9 billion adults aged 18 years and older were overweight. Of these, over 650 million adults were obese in 2016 (WHO).
Over the last thirty years, demographic, economic, environmental, and cultural shifts have impacted dietary changes in both developed and developing regions. “Nutrition transition,” termed as a combination of improved access to food and decreased physical activity level, has been identified as the prime risk factor for the increasing prevalence of overweight and chronic metabolic diseases in developing countries (Hoffman). Although advocation for healthy eating habits and lifestyle have been increasing over the past five years, there still remains a large proportion of people worldwide whose BMI index are well beyond acceptable ranges.
Current anti-obesity treatments are classified into two categories; food intake regulation (centrally acting) or by affecting the absorption of dietary fats (peripherally acting). The latter is the driving force for biomedical research in pharmaceutical drugs that could target obesity (Lunagariya et al.). One of the very few anti-obesity drugs approved by the U.S. Food and Drug Agency is Orlistat. It is an irreversible inhibitor of lipase that reduces the systemic absorption of dietary fats (Heck et al.).
However, Orlistat and other anti-obesity drugs are not available in every region that may require them, such as Libya which has 68% of its population considered obese in 2016 (WHO). Hence, it is worthy to ascertain the efficacy of natural sources of anti-obesity treatment (i.e. naturally-occurring lipase inhibitors) that could be obtained from more accessible resources in such regions. For this reason, proanthocyanidin has been chosen for this investigation since it is a ubiquitous secondary plant metabolite found in various natural sources. Through exploring how the concentration of proanthocyanidin affects lipase activity as an indication of its suitability to tackle obesity, the results could be compared with the amount of proanthocyanidin present in food sources and probe its anti-obesity potential.
In this investigation, the time taken for pH to drop by 1 unit is measured when different concentrations of proanthocyanidin solutions are added to a mixture of full-cream milk and 0.2% w/v lipase solution. It is then converted into rate at which pH drops by 1 unit for comparison across sets.