02 Feb Well-Being and Maintaining a Healthy Weight
What is the body mass index and how do we define obesity?
The body mass index (BMI) is the most commonly accepted measure of general obesity, and is one of the tests included in seafarer medical examinations. It is defined as a person’s weight in kilograms divided by the square of their height in metres (kg/m2).
Adults are classed as overweight if their BMI is between 25 and 30, obese if their BMI is 30 to 40 and morbidly obese if their BMI is 40 or more.
Why is this important?
Being overweight, and in particular being obese, markedly increases an individual’s chances of suffering from a wide range of physical and mental health problems. Notably:
- Obesity increases the risk of cardiovascular diseases and stroke
- Obesity increases the risk of type 2 diabetes
- Musculoskeletal disorders, especially osteoarthritis – a highly disabling degenerative disease of the joints – are more common among overweight people
- Many of the cancers including endometrial, breast, ovarian, prostate, liver, gallbladder, kidney and colon are linked to obesity
- besity can lead to gastroesophageal reflux, urinary stress incontinence and infertility
- Sleep disturbances like apnoea and associated breathing problems are commonly linked to obesity
- Obesity can affect quality of life and lead to psychological problems, such as depression, anxiety and low self-esteem.
These underlying conditions will almost certainly impact on a seafarer’s fitness for service and can endanger not only the health of the individual seafarer but also the onboard safety of other crew.
How significant is the problem?
Excess weight and obesity are problems that are getting worse and the World Health Organization (WHO) has reported that worldwide obesity has almost tripled since 1975. Obesity is also a problem that is becoming more widespread: whilst it still tends to be more pronounced in high-income countries, this can no longer be considered a “Western” or European problem. The WHO found that, in 2016, 39% of adults worldwide were overweight, and 13% were obese. Perhaps most surprisingly, it was found that most of the world’s population live in countries where being overweight or obese kills more people than being underweight.
There is growing evidence to suggest that unhealthy weight gains are becoming a particular problem within the maritime sector. A study of offshore personnel in the North Sea oil industry found that the body weight of the average worker had risen by almost 20% in the last 30 years. Another study, involving over 1,000 seafarers of all nationalities serving onboard Italian-flagged vessels, found that 40% were overweight and over 10% were obese. The study also found that seafarers, regardless of their nationality and rank, showed a greater tendency to be overweight and obese compared with the general population of the same ethnicity.
How does obesity happen?
Obesity is a condition that develops gradually over time. Whilst every individual’s story is different, the underlying cause of obesity is the same: an energy imbalance between calories consumed and calories expended. The average physically active man needs around 2,500 calories a day, and the average woman 2,000 calories a day, to maintain a healthy weight. Overconsumption of energy-dense foods, together with a lack of physical exercise, can soon lead to weight gain and, if not controlled, to obesity and negative effects on physical and mental health.
What does this mean for the seafarer?
Obvious medical problems should be detected during regular seafarer medical examinations, but obesity, whilst recorded, is seldom considered a reason for not declaring an individual fit for sea service.
Life at sea can be physically, and mentally, demanding, and seafarers do not have regular access to medical professionals or a wider support network of family and friends. It is therefore very important that seafarers do everything they can to optimise their physical and mental well-being. Every seafarer should ask themselves the question “Am I really fit for life at sea?” Things to consider might include: can I climb a vertical ladder? Will I fit through manhole openings? Does the Personal Protective Equipment fit me correctly? Do I fit into a lifeboat seat? Can I work for long periods in extremes of temperature, such as an engine room or a galley? Do I sleep well? If any of these things are affected by your body weight, it is time to do something about it!
Practical ways to manage your weight
- Reduce your intake of high-energy, highly processed food such as fast food, sugary drinks, sweets and alcohol
- Pay attention to your portion size – do you really need to eat such a large portion?
- Drink plenty of water, and try t odrink a large glass before every meal
- Try to eat more slowly – put your cutlery down between mouthfuls
- Try to eat at least five portions of fruit or vegetables every day – all
kinds of fruit and vegetables count, and it does not matter if they
are fresh, frozen, tinned or dried - Cut down on saturated fats, found in foods such as fatty meat,
processed meat products, cheese and butter. Try to eat more foods containing unsaturated fats, such as vegetables, legumes, nuts and oily fish - Aim to increase your fibre intake by eating more unrefined grains such as oatmeal or bran, choosing brown rice or wholemeal bread or pasta when available, and eating potatoes with their skins on
- Keep a food diary and write down everything you eat
- Get into the habit of regular physical activity – it does not have to
be intense: “a little and often” is the best way - It is recognised that shipboard life may not always allow the sea- farer to make their own choices – for instance, the daily menu is decided by the cook, and opportunities for structured physical exercise may be limited. However, it is possible to make some small choices and changes which can become “good habits” that will help you to control your weight. It is also true that seafarers tend to have fairly long vacation periods, time when good habits can be established before going back to sea.
Not every strategy works for every person but small steps, such as the above, help seafarers to achieve and preserve good health, and employers to maintain a fit, healthy and happy crew. This helps to reduce the likelihood of poor health, leading to a shortened seagoing career or a medical emergency at sea.
If you are concerned about gaining weight, do something about it – take the first small steps!
TH!NK LSR – Think about your personal well-being
Peter Chilman, QSE Manager