Is weight really a case of food intake and exercise?
There is often a perception that a high weight, is the cause of eating too much and moving too little, but it isn’t quite as simple as that. In fact, there are many factors that influence someone’s weight, and I will discuss some of these factors in this blog.
Factors affecting weight
Sleep – Sleep affects weight in many different ways. If a person doesn’t get enough sleep they may reach for higher calorie foods in a bid to get more energy . Sleep can also influence hormones, in particular hormones that influence hunger, such as ghrelin . To reduce the chances of sleep affecting weight, be sure to aim for at least 7 hours of quality sleep.
Stress – Stress releases cortisol, and a cortisol increase can cause insulin sensitivity . Not only that, stress can also lead to increased food intake. This is because some respond to stress, by eating more as a coping mechanism. Stress has also been shown to reduce peoples appetite, as the flight or fight response suggests our body focuses its energy on other functions. In order to do this, it suppresses the appetite so we have more energy to fight the stress .
Age – Weight gain is common as we age. Studies have even found that age-related weight gain occurs despite regular exercise .
Genetics – The impact of genetics on body weight is undeniable. Studies of monozygotic twins and dizygotic twins support this, as monozygotic twins have been found to be noticeably similar in weight compared to dizygotic twins . Moreover, adoption studies have found biological parents are often closer in weight range than adoptive parents in many cases .
Medications – There are plenty of medications that are known to cause weight changes or affect appetite. Some common medications affecting weight are the contraceptive pill, antidepressants and steroids.
Medical conditions – Certain medical conditions or illnesses are known to affect weight, and this is a large reason why it’s so important not to simplify weight changes as a cause of exercise and food intake. Conditions such as PCOS, under active thyroid, and Cushing’s syndrome are all commonly associated with weight gain. On the other hand, conditions such as some cancers, coeliac disease, and over active thyroid, can cause unintentional weight loss.
Social economic status – Wealth can be a large factor of weight. If someone has a low social economic status they may find themselves in lower paid work, meaning they may not be able to afford a balanced diet. Someone from a lower income may also be forced to work longer hours due to a low wage, therefore having less time to exercise or cook, so may be more likely to buy convenience food. There is a big list of ways that a persons social economic status can impact a persons weight, but those are just a couple of examples.
Sex – Someone’s sex affects weight in different ways. Typically males will be of a higher weight to females, and this is generally due to increased muscle and height. There are many studies which have investigated weight differences between sexes, and the science behind it. To summarise one aspect of this complex area, male and female hormones cause differences in the storage of weight. Males typically store weight in their abdominal area, whereas females tend to start storing weight in this area when they hit the peri menopause stage, and this is thought to be due to the decline in the oestrogen at this time .
There are of course many more factors that can influence weight than just the eight listed above, but I hope this post has dispelled the myth that weight is a case of exercise and food, because as you can see it is a little more complicated than that.
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