Obesity in America is in epidemic proportions! We as a country are getting fatter. It is estimated that two thirds of Americans are now considered overweight. This is up from 45 percent in 1960. This problem threatens to bypass smoking as the number one health hazard in America.
One third of us are considered obese which is defined as a body mass index (BMI) of greater than 30. Even more alarming is the fact that 17% of children are considered obese.
What are the causes? Obesity occurs when a person consumes more calories than he or she burns. For many people this boils down to eating too much and exercising too little. But there are other factors that also play a role in obesity. Genetics! Obesity and thinness tends to run in families. In a study of adults who were adopted as children, researchers found that participating adult weights were closer to their biological parents' weight than their adoptive parents'.
Being overweight is a risk factor for a number of health problems including diabetes, heart disease, stroke and osteoarthritis. As a result, being overweight may adversely affect the feet, ankle and legs including the knee and hip joints.
The effect of obesity on the lower extremity should come as no surprise as it is estimated that every pound of body weight puts three pounds of force through the foot while walking and as much as seven pounds when running. For example if two people, one of normal weight and the other overweight suffer the exact same injury through the same mechanism of injury, the overweight person will suffer a greater degree of injury meaning it will end up more severe. For example this could be the difference between straining a ligament versus breaking a bone.
In obese children the problem is further magnified. Children live in an environment of activity, from every day activity to athletic activity. The obese child is at a severe disadvantage. Overweight children tend to walk more slowly and with more exertion compared to normal weight children. Obese children also tend to walk with a diminished sense of balance or stability. This translates into a very quick swing phase of gait where the rear foot swings forward and a prolonged double support stance phase where both feet are on the ground. This lack of stability forces overweight children to walk more rigidly in an effort to better stabilize their gait.
Since children's bones are still forming, excessive body weight creates abnormal stresses on these forming bones and can result in less development in the arch of the foot. Some experts recommend putting all overweight kids in orthotics to control the formation of the arch of the foot, while others only recommend orthotics for symptomatic children.
To make matters worse, overweight people may suffer from metabolic syndrome which can slow the healing process. Going back to the example earlier, this means not only will the overweight person require more time to heal because of a more severe injury than the normal weight person, but the overweight person’s metabolism will further delay the healing process because in the metabolic syndrome the body is not working at its optimum capability.
Scientists have found a direct correlation between obesity and pathology of the lower extremity. Carrying added in weight in an individual who tends to pronate, may lead to chronic heel pain.
So why am I writing about obesity? It should be clear that there is a direct connection between some foot and ankle pathology and excessive weight. This occurs on two fronts. One is the biomechanical abnormalities that I have already discussed such as being more prone to worse injuries and being more susceptible to chronic type of foot and ankle pains.
Additionally, overweight people have a greater tendency to become type II diabetics. Most disconcerting is the fact that there has been a substantial rise in diabetes among our youth; those ages between 10 and 19 years. (1)
As obesity relates in everyday practice, I see many people with a variety of foot and ankle problems who happen to be overweight. In spite of all the treatment protocols available to me for various conditions, one central fact remains. Unless these people lose weight, their lower extremity problems are not going to totally resolve themselves and even if we are lucky in eradicating a problem, those that are overweight have a much greater chance of redeveloping the same problem.
In many circumstances where I feel the major catalyst to the particular problem a patient presents with is their weight, I am point blank about that fact. I tell these patients that I am not a magician and unless something is done about their excess weight this particular problem (and others) will continue to plague them.
I have seen this hundreds of times over my career where excess weight and foot and ankle problems lead to a vicious cycle of pain, leading to diminished activity, leading to further weight gain, leading to even less activity.
So, for those of you reading this article and who happen to be overweight suffering from the same cycle and problems above, I cannot emphasize how important it is to take charge of your life and do what ever it takes to lose that weight. I cannot speak as an expert on how obesity affects the rest of your body, but I will tell you this; over time the foot and ankle will continue to degenerate and only get worse and whereas there may be treatments that were once helpful for your foot or ankle problem, eventually even those treatments will become less effective.
1. NIH. Statistics related to overweight and obesity, Accessed at: NIH Statistics