Fat Science

‘Three-year-old dies of obesity’  screamed the newspaper headlines  when, in May 2004, a child died from  heart failure in a London hospital.  She weighed a staggering 40 kg.  A media frenzy erupted, and the  parents were blamed for ‘stuffing  her to death’.  Was it fair to accuse her parents?  Scientists later confirmed that there  was a medical problem behind the  child’s extreme obesity: a genetic glitch  that triggered her immense appetite. Genes play a crucial role in shaping  our weight, but scientists have only  recently started to work out how.  It is too simple to say that obesity  is ‘all in the genes’ but our genetic inheritance does have a big say in  our size. Researchers can come at obesity f rom two directions. In a ‘classical’  approach, the extent to which  weight or obesity is inherited can  be assessed. This is a difficult area  to study, but the consensus i...

Does Obesity Matter? Worldwide obesity has more than doubled since 1980. In 2014, more than 1.9 billion adults, 18 years and older, were overweight. Of these over 600 million were obese. 39% of adults aged 18 years and over were overweight in 2014, and 13% were obese. Most of the world's population live in countries where overweight and obesity kills more people than underweight. 41 million children under the age of 5 were overweight or obese in 2014. Obesity is preventable. Raised BMI is a major risk factor for noncommunicable diseases such as: cardiovascular diseases (mainly heart disease and stroke), which were the leading cause of death in 2012; diabetes; musculoskeletal disorders (especially osteoarthritis – a highly disabling degenerative disease of the joints); some cancers (including endometrial, breast, ovarian, prostate, liver, gallbladder, kidney, and colon). The risk for these noncommunicable diseases increases, with increases in BMI. Childhood obes...

Too much fat: According to the World Health Organisation (WHO): Worldwide obesity has more than doubled since 1980. In 2014, more than 1.9 billion adults, 18 years and older, were overweight. Of these over 600 million were obese. 39% of adults aged 18 years and over were overweight in 2014, and 13% were obese. Most of the world's population live in countries where overweight and obesity kills more people than underweight. 41 million children under the age of 5 were overweight or obese in 2014. Obesity is preventable. But what is obesity? Overweight and obesity are defined as abnormal or excessive fat accumulation that may impair health. Body mass index (BMI) is a simple index of weight-for-height that is commonly used to classify overweight and obesity in adults. It is defined as a person's weight in kilograms divided by the square of his height in meters (kg/m 2 ).  BMI is best used as a guide line as it can be inaccurate. For example athletes have a h...

Fat Functions: In previous week we have already looked at the role of omega-3 and cholesterol in the body. This week we are going to overview functions of lipids in the body and ensure we have a full understanding and appreciation of their importance to living things. 1 . Lipids are a an incredible source of energy  for living organisms. Gram for gram fats release twice as much energy as carbohydrates and it also releases valuable water in the process. In order to become a fuel for respiration triglycerides are split into their main substituent parts; glycerol and fatty acids. For  those of you that are familiar with the process of cellular respiration t he glycerol molecule is split and is incorporated into the glycolysis pathway and the 3 fatty acid chains are also split by enzymes before joining the krebs cycle . The reason fats release more energy is because as the fatty acids are broken down they are oxidised , losing  hydrogen. These ...

Close-up on Cholesterol: Cholesterol belongs to a family of lipids called steroids, which have a common structure (see diagram above), very different to the triglycerides we have met before.  Our notion of cholesterol as bad is overly simplistic. When we say "cholestrol" we are actually referring  to two different cholesterol transporters found in the blood: high-density and low-density lipoprotein, otherwise known as HDL (‘good’) and LDL (‘bad’) cholesterol.  Raised levels of LDL cholesterol are generally associated with an  increased risk of heart disease. According to most sources, it is not eating high-cholesterol foods, such as eggs, that drives up our blood cholesterol levels, but eating foods that are high in saturated fats. This is because our livers turn saturated fats like those in cakes and pastries into LDL cholesterol in the blood. The past few years have seen continued questioning of dietary guidance on saturated fats and cholesterol...