It is often assumed that science occurs in laboratories and that the use of science is reserved for those with doctorates or specialist training. But in reality science is just the observation of phenomena and the use of these observations to make sense of the World around us. In this regard, science can be performed anywhere by anyone with a keen eye and an unbiased and open mind. Much of our current understanding on nutrition and how it affects human metabolism and physiology has originated from high cost studies performed by research specialists groups. However, observing people and their eating habits can often provide important insights into the feeding behaviors of humans and how this impacts their health. Standing in line at a supermarket and observing the food placed on the checkout by an individual is a snapshot into their eating habits and can provide a wealth of data that is not really any different in essence to the complex food diaries used in academic literature.
Watching people eating lunch can also be enlightening. Just last week there was a group of individuals close to me at lunch eating what can only be described as a big bag of junk. In the bag was crisps, chocolate bars, sandwiches and other confectionary. Judging by the shape and size of one of the individuals in the group it is likely correct to assume that considerable metabolic damage had already been done through consumption of such food for a reasonable length of time. For although clothes can hide a multitude of sins, the classic abdominal obesity that originates from hepatic insulin resistance and the accumulation of fatty acids in the viscera of the abdomen is easy to spot. It is often assumed that weight gain is caused by the overconsumption of energy. However, evidence suggests that rather than how much we eat, it is what we eat that causes weight gain and obesity. Low quality foods cause metabolic damage, and this leads to aberrations in appetite and energy regulation and ultimately weight gain.
So what are the metabolic costs of eating this big bag of junk? Well chocolate bars tend to contain sugar, which comprises of fructose and glucose. Evidence suggests that large intakes of fructose in the absence of fibre, such as might be found in chocolate bars, can overload the liver with energy because the energy from the food is absorbed too quickly. Only the liver can metabolise fructose, and some of it used to resynthesise glycogen. However, large intakes of fructose in the absence of depleted glycogen results in a shift in metabolism to that of increased production of fatty acids. These fatty acids accumulate in liver and skeletal muscle tissue and here they interfere with the insulin signal cascade. This leads to the development of central and peripheral insulin resistance. Over production of fatty acids also increases the deposition of triglycerides in the liver and viscera leading to the development of abdominal obesity. Hence the android body shape of one of the individuals eating the bag of junk.
Crisps too are low quality foods as they contain altered and modified fats. Increasingly crisps are made with polyunsaturated fats that the manufacturers claim to be beneficial in comparison to saturated fat. However, the polyunsaturated oils used in manufacturing crisps is usually sunflower oil, an omega 6 fatty acid. Current opinion is that Westerners eat too much omega 6 fat and too little omega 3 fat. This is important because for health the omega 6 to omega 3 ratio is recommended to be around 3 to 1. However, the oversupply of omega 6 fatty acids in processed foods such as crisps, and the depletion of virtually all omega 3 fats from the diet, has caused the Western diet to possess a ratio of omega 6 to omega 3 fats that is nearer to 10 or 20 to 1. This imbalance in the omega 3 to omega 6 ratio leads to the production of proinflammatory eicosanoids which in turn causes systemic inflammation. Over time this inflammation increases oxidative stress, which ultimately causes diseases such as cardiovascular disease and cancer.
Crisps also contain hydrogenated and trans fats which are created during the manufacture of the processed polyunsaturated oils used in cooking the crisps. These modified fats interfere with essential fatty acid pathways and aggravate inflammation through creation of an essential fatty acid deficient state. This is because the fats can interact with the enzymes in essential fatty acid pathways and thus interfere with normal eicosanoid production. Pre-prepared sandwiches in packets are a popular choice at lunchtime and many believe they are picking a healthy option. However, pre-prepared packet sandwiches also often contain spreads and margarine which contain processed and modified omega 6 fatty acids. The sandwiches in the big bag of junk would therefore likely have contributed to dysfunction in normal inflammatory pathways in those eating them. In addition, sandwiches can also contain processed meats, preservatives and other ingredients that can contribute to inflammation and oxidative stress.
Another problem with pre-packaged sandwiches is the overly processed bread that is used in such items. Fully refined white bread is devoid of all meaningful levels of nutrients and can contribute significantly to the development of insulin resistance. This results from the lack of fibre in combination with the low content of trace minerals. The lack of fibre increases postprandial glycaemia and over time the frequent rapid rises in insulin contribute to the development of insulin resistance. The lack of important trace minerals in refined white bread also reduces insulin sensitivity. For example, the insulin receptor cannot function without chromium as a cofactor, and frequent consumption of chromium depleted foods such as white bread can lead to a chromium deficient state. Even the whole grain bread used in some sandwiches may be detrimental because the bread is over often milled which destroys the cells walls, the presence of which is necessary to slow the digestion of the starch within.
So low quality foods cause metabolic dysfunction and this leads to changes to the normal energy metabolism through the development of insulin resistance. In addition, low quality foods also bypass normal appetite regulatory mechanisms. This can lead to overeating which many might claim is the cause of the weight loss. However, overeating low quality foods also accelerates the damage these foods cause and this maybe the real reason that weight gain and abdominal obesity ensue. Junk food lead to a junk metabolism, and a big bag of junk food leads to a big deterioration in metabolic function. The one redeeming fact was that the big bag of junk did not contain soft drinks which are particularly high in fructose, particularly low in fibre and macronutrients, and therefore particularly damaging to the health. Exercise can help minimise the damage from such foods, but even with exercise the metabolic damage from regular consumption of such junk will catch up with the individual causing them to get fat.
Dr Robert Barringtons Nutritional Recommendation: If your health is important you should avoid buying and consuming junk food. A big bag of chocolate, sweets crisps and refined foods is a fast track to poor health and misery. The good news is that the metabolic damage caused by junk can be reversed by consuming a high quality foods. High quality foods rich in fibre, micro nutrients and antioxidants reverse insulin resistance and slowly return normal function to energy metabolism and appetite pathways. A traditional diet such as the Mediterranean diet is therefore a weight loss diet, because it is the antithesis to the weight gain caused by junk food.
RdB
