A healthy lifestyle includes eating a variety of foods, physical activity and maintaining a healthy body weight.

Obesity

“like anything in life, the key is moderation”

Obesity is used to describe a person who is very overweight.  There is an association between obesity and lifestyle diseases including diabetes, high blood pressure and heart disease.

Studies show that the majority of South Africans eat high amounts of fat combined with too little vegetables, dairy and legumes, and too much refined and processed food and these calories are not being burnt off.  In ancient times man used huge amounts of energy daily to hunt and forage for food, among other activities. What food they could get was also unrefined and hard to digest.  Our modern lifestyle is becoming more and more sedentary, while a huge variety of highly processed foods is available, and acquiring food does not require us to spend a lot of energy.

 

What causes weight gain?

Weight gain is caused by the imbalance between calories eaten and calories burned off in everyday activities, according to the World Health Organisation.

 

All foods provide calories.

1 gram of protein – 16.8kJ (4 calories)

1 gram of carbohydrate – 16.8kJ (4 calories)

1 gram of fat – 37.8kJ (9 calories)

 

Sugar is a carbohydrate so 1 gram of sugar provides 16.8kJ (4 calories). Sugar itself does not cause weight gain more so than any other type of food. Remember though, it is important to enjoy a healthy diet that has variety and includes fresh fruit and vegetables, protein such as fish, chicken and lean meat, and carbohydrates such as potatoes, rice, cereals as well as including legumes, lentils and whole grains. Have a look at the South African Guidelines for Healthy Eating or talk to your doctor or a registered dietitian.

Eating more calories than you use each day can lead to weight gain over time. If you need to lose weight, a slow and steady approach is needed for long-term success. The total number of calories you eat and the amount of physical activity you do over several days is what is most important. A person who sits most of the day and eats more calories than they burn will gain weight.

The Body Mass Index (BMI) is a formula that is used to generally indicate if a person may be overweight (or underweight), and if so, to what extent.  The purpose of this is further to determine your potential health risk, linked to possible obesity.  It is always important to consult with a doctor and a registered dietitian concerning health, weight and dietary recommendations.

BMI is calculated by dividing your weight, in kilograms (kg), by the square of your height in metres (m2).

Here is a BMI calculator, which is a popular tool that you can use to simply calculate your BMI.

BMI Calculator

Type your weight in kilograms here:

Type your height in centimetres here:

Body Mass Index (BMI) is a useful tool for adults 18 years and older to know whether you weigh too much for your height. If your BMI is between 18,5 – 24,9 your weight is normal. If it is equal to or greater than 25 but less than 30, you are overweight; and if it equal to or greater than 30, you will be classified as obese. The higher your BMI, the greater the risk is of developing complications such as diabetes, heart disease, stroke and some cancers.

BMI range -kg/m2 Weight Status
Below 18,5 Underweight
18,5 – 24,9 Normal
25,0 – 29,9 Overweight
30,0 and above Obese

Interesting studies about sugar and obesity

In 2011, an analysis of the changes in sugar consumption and obesity over the past 30 years in Australia was reported.  The evidence showed that while Australians reduced their sugar consumption by 23% since 1980 obesity increased 300% over the same period.

The analysis also confirmed that the consumption of sugar has decreased in both the United States by 20 percent and the United Kingdom by 10 percent since 1980. The term “Australian Paradox” was adopted to describe this contradiction.

This study shows that systematic efforts to reduce sugar intake is an ineffective public health strategy to reduce the prevalence of obesity. Emphasis on reducing a single dietary component, like sugar or any other food, ignores the complexities of obesity and slows resolution of its detrimental public health consequences.

A 3-year study conducted by The National Academy of Sciences concluded, “There is no clear and consistent association between increased intakes of added sugars and BMI.” The BMI (Body Mass Index) is an indicator of body weight and obesity.

Interestingly, research has shown that those wanting to lose weight found diets that included sugar easier to follow than diets that did not contain sugar.  Scientists conducting the study concluded that sugar improved adherence to the diet because of the taste it added to food.

Diabetes

“the belief that sugar causes diabetes is a common misconception”

Diabetes is a condition that affects the way a person’s body uses blood glucose (blood sugar). Diabetes cannot be cured, but it can be managed through diet, lifestyle and medication. Type 1 diabetes is diagnosed when a person has no insulin produced by their body. The reason for this occurring is not known. It may start in early infancy or later in life. Type 2 diabetes is characterised by a gradual decrease in the effectiveness of the action of insulin. Type 2 diabetes used to occur in older people, but is now also found in children and adolescents, especially when they are overweight and inactive.

 

What is insulin?

Insulin is a hormone, normally produced in the pancreas in response to elevated blood glucose levels, such as after eating a meal with carbohydrate containing foods. People with undiagnosed diabetes will have high blood glucose levels, as insulin has not moved the sugar from the blood to the muscles or to storage. They will have a shortage of glucose in their organs and muscles, as insulin has not transported the glucose from the blood to the sites where it is needed.

 

Does eating sugar cause diabetes?

The reason why many people think that eating sugar causes diabetes is probably linked to this historical diet advice. It may also be due to the colloquial name for diabetes mellitus, which is ‘blood sugar’ or possibly explained as ‘too much sugar in the blood’. There is no evidence that refined sugar has any unique attributes that result in the development of diabetes.

The belief that eating sugar causes diabetes is the most common misconception about diabetes. What does predispose a person to diabetes is genetics, being overweight and leading an unhealthy lifestyle such as not doing enough physical activity and poor eating habits. Avoiding sugar will not stop a person from getting diabetes. If you have a family history of diabetes, the best way to avoid developing diabetes is to be physically active, have good eating habits and avoid weight gain.

 

The use of sugar in healthy eating plans for people with diabetes

The management of diabetes aims to achieve and maintain blood glucose levels within healthy ranges. Decades ago it was believed that refined sugar and products made with refined sugar would cause blood sugar levels to rise rapidly and then fall rapidly. This was contrary to the objective of disease management, and hence people diagnosed with diabetes were told not to eat refined sugar, and foods made with refined sugar.

In the 1980s scientists tested the body’s response to sugar consumption by taking measurements of blood glucose, at frequent intervals, after research subjects ate it in a controlled situation. Many other carbohydrate containing foods were also tested, and ironically it was found that some foods with starch (complex carbohydrates such as potatoes) caused a more rapid blood glucose response than did refined sugar. This information has slowly been incorporated into advice given to people with diabetes about healthy eating. So people with diabetes can include sugar as part of their carbohydrate requirements for the day.

Oral health

Oral health is the health of your teeth, gums, tongue and mouth. Oral health care is an important part of overall health care.

A cavity is the medical word used to describe holes in our teeth. The process starts when we eat carbohydrates and some of the food is left behind on our teeth which becomes plaque. Organic acids are formed and this causes dental caries. Sugar is a carbohydrate so is associated with dental caries. For advice about oral health care, consult your local healthcare practitioner.

You help prevent cavities by getting rid of the bacteria in plaque. Clean your teeth very well, twice a day. Rinse your mouth with water after eating to remove some of the little bits of food.

Food addiction

There has been some discussion on the possibility of food addiction.  In the article below, the issue is explored by David Benton, a Professor of Psychology at the University of Swansea in the United Kingdom.  He specialises in the study of the influence of nutrition on psychological functioning. Professor Benton helps us to understand why the NeuroFAST consortium, funded by the European Union, concluded that a single food substance cannot account for overeating and obesity.

A review that looked for the symptoms of addiction such as withdrawal, craving and tolerance could find no evidence of an association with sugar consumption (Benton, 2010).

There is currently no strong evidence that individuals become addicted to chemical substances in foods and the brain differs in the way it responds to food and addictive drugs such as heroin or cocaine.

Addiction is a powerful force that can take control of the lives of users. In the past, addiction was thought to be a weakness of character, but in recent decades research has increasingly found that addiction to drugs like cocaine and heroin is a matter of brain chemistry.

Addiction is a chronic, brain disease that causes drug seeking and use, despite harmful consequences to the addicted individual and to those around him or her. Although the initial decision to take drugs is voluntary for most people, the brain changes that occur over time challenge an addicted person’s self-control and hamper the ability to resist intense impulses to take drugs.

The way a brain becomes addicted to a drug is related to how a drug increases levels of the chemical dopamine. Dopamine controls movement, emotion, motivation and feelings of pleasure. The pleasure sensation that the brain gets when dopamine levels are raised creates the motivation for us to proactively perform actions that are indispensable to our survival (like eating or procreation). Dopamine is what conditions us to do the things we need to do.

Using addictive drugs floods the brain with dopamine—taking it up to as much as five or 10 times the normal level. With these levels elevated, the user’s brain begins to associate the drug with an oversized reward. Over time, by artificially raising the amount of dopamine our brains think is “normal,” the drugs create a need that only they can meet. That leads to the process of addiction, wherein a person loses control and is left with an intense drive to compulsively take the drug.

Human evolution has been associated with the development of a genetically based liking for a sweet taste. Breast milk is sweet: we are born liking a sweet taste. Such data puts the current worry that sugar may be addictive into perspective. It has been proposed that physical addiction to sugar may develop as it stimulates the release of dopamine which causes a “happy feeling” via the brain’s reward system. Yet although sweet foods stimulate reward pathways in the brain, such responses should not be confused with addiction.  Drugs of abuse, such as cocaine, hijack the normal reward pathways and act in a different way to a normal response to a palatable food.

Those studying physical addiction to drugs of abuse distinguish ‘wanting’ from ‘liking’, two mechanisms that reflect different circuits in the brain.  When addicted the release of dopamine is associated with ‘wanting’ a substance, it is motivating and may be associated with cravings. In contrast, ‘liking’, that is a resulting pleasant experience, is associated with the release of opioids by the brain. As any pleasant event, even a joke or a smile, will cause the release of dopamine release, inevitably palatable food releases dopamine. This is a normal response.

However, neurophysiological techniques, that monitor the firing of brain cells, have been used to study the impact of consuming sugar on the release of dopamine and find that the pattern differs from drugs of abuse. With sucrose less dopamine is released prior to consumption than with drugs of abuse.  Once eating becomes a habit or when we adapt to eating, the initial release of dopamine declines and in addition the release of dopamine stops when eating begins. As the release of dopamine declines the motivation to eat ‘a second or third piece of cheese cake’ falls rapidly. With drugs of abuse, dopamine is released for longer, in larger amounts, and occurs both before and after consumption. This is an important difference as it is the presence of dopamine that induces the motivation to consume and the prolonged release of dopamine with drugs of abuse increases intake.

Particular attention has been drawn to brain imaging studies in which a low level of dopamine receptors has been found in the obese, in a similar manner to those addicted to drugs of abuse. However, a recent large scale study found that the number of dopamine receptors was not associated with obesity in either children or their mothers (Hardman et al., 2014).

A review that looked for the symptoms of addiction such as withdrawal, craving and tolerance could find no evidence of an association with sugar consumption (Benton, 2010).  The NeuroFAST consortium, funded by the European Union, concluded that a single food substance cannot account for overeating and obesity (Hebebrand et al., 2014). There was no strong evidence that individuals become addicted to chemical substances in foods and the brain differs in the way it responds to food and addictive drugs such as heroin or cocaine. They suggested the term “eating addiction” rather than “food addiction”; that is some people develop a psychological compulsion to eat, driven by the positive feelings associated with eating: the focus should be moved from food itself towards the individual’s relationship with eating. Thus attempts to deal with obesity should concentrate not so much with food but rather the individual’s relationship with eating. This is an important distinction as a ‘food addiction’ approach sees obesity as a passive process that befalls the individual when palatable foods are eaten. However, the incidence of obesity differs in those with a similar access to food: some are able to control their weight, whereas others cannot. The ‘eating addiction’ approach stresses the need to consider psychological differences in the ability to deal with food.

The Benefits of Exercise

We all know physical activity is good for us, but what exactly are the benefits and what do we need to do? The KwaZulu-Natal Regional Chairwoman of the Biokinetics Association of South Africa (BASA), Tas Chetty, B.A (Hons) Sport Science; BA (Hons) Biokinetics, gives us the facts.

 

How does physical activity promote, maintain or improve a person’s health?

  • It is beneficial for the management of chronic diseases such as diabetes, hypertension, and osteoporosis.
  • Exercise lowers excessively high glucose levels, increases insulin sensitivity, reduces the amount of LDL cholesterol and lowers blood pressure.
  • Regular exercise keeps your heart and lungs healthy, muscles strong and toned, it improves posture, aids in the management of weight through increased energy expenditure, and improves the quality of sleep.
  • Exercise is a type of stress, a good stress. This stress causes the body to adapt and improve to overcome this new load placed on the body.

 

How much physical activity would a person need to participate in to enjoy health benefits?

  • The American College of Sports Medicine’s minimum basic recommendations are 150 minutes of moderate-intensity cardiovascular exercise per week; all major muscle groups should undergo resistance training two to three times per week; flexibility exercises should also be completed two to three times per week.
  • Having said that, any exercise is better than none. It is vital to keep moving. Remember, movement = medicine.

 

Would you say that physical activity is also good for mental health and if so how?

  • Exercise increases serotonin and dopamine production, which are neurotransmitters in the brain. Serotonin decreases depression and hostile behaviour. Dopamine aids in enhancing an individual’s mood and improves long term memory.
  • Exercise increases blood flow, thus delivering fresh oxygen rich blood to the brain which leads to improved cognition.
  • Exercise enhances an individual’s body image which increases self-confidence and general satisfaction.
  • Engaging in exercise may also be a social activity for some which has further benefits of mood and mental health.

 

Are there specific health benefits linked to specific types of exercises?

  • Resistance training improves muscle strength and endurance and tones or firms the muscles. It also aids in controlling neuromuscular pain, or musculoskeletal pain such as neck or back pain.
  • Cardiovascular exercises primarily improves heart and lung function. The efficiency of the cardiorespiratory system gets improved which aids various conditions such as hypertension, COPD and post-MI’s.
  • Flexibility exercises improve range of motion and aids in muscle recovery when done after a training session. It also helps keep muscles in balance which can lead to improved posture.

 

Please provide information about heart rate. One often hears that this is a mark of fitness, is this true?

  • Heart rate is the number of times that your heart beats per minute. A normal heart rate for adults at rest is anything between 60-100 bpm.
  • The heart rate does not indicate absolute fitness, however in fit individuals the heart generally beats less per minute because as cardio fitness increases the heart will pump more blood per beat (due to increased blood volume and increased contractility of the heart muscle). This means that the heart doesn’t have to beat as fast or work as hard to meet the demands of a given activity.
  • A lower resting heart rate means an individual will not tire as quickly; he/she will have more in reserve. Heart rate recovery is another parameter closely related to fitness, as it indicates how effectively and quickly the heart can recover and return to a resting state post-activity.
  • Heart rate is also important in controlling exercise intensity. Working at certain percentages of your maximum heart rate provides different adaptations. Training to improve cardio fitness should be between 70 – 80% of your max heart rate, while fat burning takes place slightly below this at 60 – 70%. Maximum heart rate can be worked out by the formula 220 – Age.

 

When a person is trying to lose weight, what would be the best exercise option? Some say cardio others say weight training?

  • A combination of cardio and resistance training is most beneficial for weight loss as this utilises large muscles groups or a number of different muscles groups at the same time which has a higher energy expenditure.
  • During steady state cardio training at an intensity of 60 – 70% fat burning occurs. Resistance training aids in increasing basal metabolic rate due to increases in muscle mass thus increasing energy expenditure even when a person isn’t exercising. Making sure that you get both of these training methods into your routine is beneficial.
  • There has been a trend to utilise cardio-strength training or High Intensity Interval Training. This requires individuals to fluctuate between short high intensity periods of work, and equal or shorter periods of rest.
  • This type of combo training has been shown to have higher energy consumption rates after an exercise session when compared to steady state cardio exercise, thus enhancing weight loss.

 

If a person overweight does weight training can that fat can get trapped between the muscles?

  • Fat is stored in various compartments around the body. There is visceral fat which surrounds the organs, subcutaneous fat which is under the skin and intramuscular fat which is found within the muscles.
  • The body will draw from these stores to provide fuel for its activities. One of the first stores that it utilises is the intramuscular fat. This is one of the reasons why muscles will start to feel firmer and more toned upon starting exercise.
  • Subcutaneous fat and then visceral fat follows once intramuscular stores are low.

 

When a person is trying to lose weight how important is physical exercise for this – besides the health benefits?

  • A combination of exercise and proper nutrition will yield the best results for weight loss. There will be improvements with just one or the other, but the improvements will be much larger when combining the two.
  • Weight loss isn’t going to happen if you train hard but then fill up with the wrong foods.
  • Losing weight comes down to trying to burn as much stored energy as possible. Exercise increases energy expenditure while proper nutrition ensures that you’re not storing more energy than you need.

 

When partaking in exercise what sort of food groups or types of foods would be beneficial and at what times?

  • It depends on what the individual is training for. Weight loss nutrition would be different to how an athlete would eat, and these would both be different to the nutrition strategy of a body builder.
  • Generally speaking, when exercising, the body will need complex carbs (green vegetables and wholegrains) and protein for adequate energy during the session and to support muscle growth and recovery after the session.
  • It’s best to space meals out every 3 – 4 hours to ensure that glucose levels are steady throughout the day. Spacing meals too far apart causes large insulin spikes which promotes fat storage.
  • Within 30 minutes after exercise, it is also beneficial to take in a meal with 30 – 40 grams of carbs and 10 – 15 grams of protein. This aids muscle growth and repair.

 

What tips could you give to a person to increase their physical activity and their fitness level regardless of where it is at?

  • Exercise is a long term game. It takes time for the body to adapt so don’t be disheartened if you don’t see a six pack in one week. Start slowly and progress gradually.
  • It has to become habitual and ingrained into your daily routine. A large part of the game is won if you muster the discipline to stick to a steady routine and weave it into the fabric of your day.
  • Remember to change your exercise programme every two to three weeks. This aids in taking your fitness to its next stage and keeps the body from plateauing. If you do the same thing over and over again the body will adapt at first to meet the requirements and then just maintain that level unless you hit it with something different.
  • Avoid inactivity by making a conscious effort to be active, for example; avoiding the lift in malls and using the stairs instead, parking slightly further and increasing the distance you need to walk to reach your destination.
  • Speak to a biokineticist about an exercise programme designed to meet your needs.

References

Benton (2010) The plausibility of sugar addiction and its role in obesity and eating disorders. Clinical Nutrition 29, 288-303.
Hardman et al. (2014) Lack of association between DRD2 and OPRM1 genotypes and adiposity. International Journal of Obesity 38, 730–736
Hebebrand et al. (2014). “Eating addiction”, rather than “food addiction”, better captures addictive-like eating behaviour. Neuroscience & Biobehavioral Reviews 47, 295–306.