One of the earliest descriptions of someone with cancer comes from the fourth century BC. Satyrus, tyrant of the city of Heracleia on the Black Sea, developed a cancer between his groin and scrotum. As the cancer spread, Satyrus had ever greater pains. He was unable to sleep and had convulsions.

Advanced cancers in that part of the body were regarded as inoperable, and there were no drugs strong enough to alleviate the agony. So doctors could do nothing. Eventually, the cancer took Satyrus’ life at the age of 65.

Cancer was already well known in this period. A text written in the late fifth or early fourth century BC, called Diseases of Women, described how breast cancer develops:

hard growths form […] out of them hidden cancers develop […] pains shoot up from the patients’ breasts to their throats, and around their shoulder blades […] such patients become thin through their whole body […] breathing decreases, the sense of smell is lost […]

Other medical works of this period describe different sorts of cancers. A woman from the Greek city of Abdera died from a cancer of the chest; a man with throat cancer survived after his doctor burned away the tumour.

Where does the word ‘cancer’ come from?

The word cancer comes from the same era. In the late fifth and early fourth century BC, doctors were using the word karkinos – the ancient Greek word for crab – to describe malignant tumours. Later, when Latin-speaking doctors described the same disease, they used the Latin word for crab: cancer. So, the name stuck.

Even in ancient times, people wondered why doctors named the disease after an animal. One explanation was the crab is an aggressive animal, just as cancer can be an aggressive disease; another explanation was the crab can grip one part of a person’s body with its claws and be difficult to remove, just as cancer can be difficult to remove once it has developed. Others thought it was because of the appearance of the tumour.

The physician Galen (129-216 AD) described breast cancer in his work A Method of Medicine to Glaucon, and compared the form of the tumour to the form of a crab:

We have often seen in the breasts a tumour exactly like a crab. Just as that animal has feet on either side of its body, so too in this disease the veins of the unnatural swelling are stretched out on either side, creating a form similar to a crab.

Not everyone agreed what caused cancer

In the Greco-Roman period, there were different opinions about the cause of cancer.

According to a widespread ancient medical theory, the body has four humours: blood, yellow bile, phlegm and black bile. These four humours need to be kept in a state of balance, otherwise a person becomes sick. If a person suffered from an excess of black bile, it was thought this would eventually lead to cancer.

The physician Erasistratus, who lived from around 315 to 240 BC, disagreed. However, so far as we know, he did not offer an alternative explanation.

How was cancer treated?

Cancer was treated in a range of different ways. It was thought that cancers in their early stages could be cured using medications.

These included drugs derived from plants (such as cucumber, narcissus bulb, castor bean, bitter vetch, cabbage); animals (such as the ash of a crab); and metals (such as arsenic).

Galen claimed that by using this sort of medication, and repeatedly purging his patients with emetics or enemas, he was sometimes successful at making emerging cancers disappear. He said the same treatment sometimes prevented more advanced cancers from continuing to grow. However, he also said surgery is necessary if these medications do not work.

Surgery was usually avoided as patients tended to die from blood loss. The most successful operations were on cancers of the tip of the breast. Leonidas, a physician who lived in the second and third century AD, described his method, which involved cauterising (burning):

I usually operate in cases where the tumours do not extend into the chest […] When the patient has been placed on her back, I incise the healthy area of the breast above the tumour and then cauterize the incision until scabs form and the bleeding is stanched. Then I incise again, marking out the area as I cut deeply into the breast, and again I cauterize. I do this [incising and cauterizing] quite often […] This way the bleeding is not dangerous. After the excision is complete I again cauterize the entire area until it is dessicated.

Cancer was generally regarded as an incurable disease, and so it was feared. Some people with cancer, such as the poet Silius Italicus (26-102 AD), died by suicide to end the torment.

Patients would also pray to the gods for hope of a cure. An example of this is Innocentia, an aristocratic lady who lived in Carthage (in modern-day Tunisia) in the fifth century AD. She told her doctor divine intervention had cured her breast cancer, though her doctor did not believe her.

From the past into the future

We began with Satyrus, a tyrant in the fourth century BC. In the 2,400 years or so since then, much has changed in our knowledge of what causes cancer, how to prevent it and how to treat it. We also know there are more than 200 different types of cancer. Some people’s cancers are so successfully managed, they go on to live long lives.

But there is still no general “cure for cancer”, a disease that about one in five people develop in their lifetime. In 2022 alone, there were about 20 million new cancer cases and 9.7 million cancer deaths globally. We clearly have a long way to go.

Konstantine Panegyres, McKenzie Postdoctoral Fellow, Historical and Philosophical Studies, The University of Melbourne

This article is republished from The Conversation under a Creative Commons license. Read the original article.

It’s a well-known fact that to lose weight, you either need to eat less or move more. But how many calories do you really need to cut out of your diet each day to lose weight? It may be less than you think.

To determine how much energy (calories) your body requires, you need to calculate your total daily energy expenditure (TDEE). This is comprised of your basal metabolic rate (BMR) – the energy needed to sustain your body’s metabolic processes at rest – and your physical activity level. Many online calculators can help determine your daily calorie needs.

If you reduce your energy intake (or increase the amount you burn through exercise) by 500-1,000 calories per day, you’ll see a weekly weight loss of around one pound (0.45kg).

But studies show that even small calorie deficits (of 100-200 calories daily) can lead to long-term, sustainable weight-loss success. And although you might not lose as much weight in the short-term by only decreasing calories slightly each day, these gradual reductions are more effective than drastic cuts as they tend to be easier to stick with.

Hormonal changes

When you decrease your calorie intake, the body’s BMR often decreases. This phenomenon is known as adaptive thermogenesis. This adaptation slows down weight loss so the body can conserve energy in response to what it perceives as starvation. This can lead to a weight-loss plateau – even when calorie intake remains reduced.

Caloric restriction can also lead to hormonal changes that influence metabolism and appetite. For instance, thyroid hormones, which regulate metabolism, can decrease – leading to a slower metabolic rate. Additionally, leptin levels drop, reducing satiety, increasing hunger and decreasing metabolic rate.

Ghrelin, known as the “hunger hormone”, also increases when caloric intake is reduced, signalling the brain to stimulate appetite and increase food intake. Higher ghrelin levels make it challenging to maintain a reduced calorie diet, as the body constantly feels hungrier.

Insulin, which helps regulate blood sugar levels and fat storage, can improve in sensitivity when we reduce calorie intake. But sometimes, insulin levels decrease instead, affecting metabolism and leading to a reduction in daily energy expenditure. Cortisol, the stress hormone, can also spike – especially when we’re in a significant caloric deficit. This may break down muscles and lead to fat retention, particularly in the stomach.

Lastly, hormones such as peptide YY and cholecystokinin, which make us feel full when we’ve eaten, can decrease when we lower calorie intake. This may make us feel hungrier.

Fortunately, there are many things we can do to address these metabolic adaptations so we can continue losing weight.

Weight loss strategies

Maintaining muscle mass (either through resistance training or eating plenty of protein) is essential to counteract the physiological adaptations that slow weight loss down. This is because muscle burns more calories at rest compared to fat tissue – which may help mitigate decreased metabolic rate.

Gradual caloric restriction (reducing daily calories by only around 200-300 a day), focusing on nutrient-dense foods (particularly those high in protein and fibre), and eating regular meals can all also help to mitigate these hormonal challenges.

But if you aren’t someone who wants to track calories each day, here are some easy strategies that can help you decrease daily calorie intake without thinking too much about it:

1. Portion control: reducing portion sizes is a straightforward way of reducing calorie intake. Use smaller plates or measure serving sizes to help reduce daily calorie intake.

2. Healthy swaps: substituting high-calorie foods with lower-calorie alternatives can help reduce overall caloric intake without feeling deprived. For example, replacing sugary snacks with fruits or swapping soda with water can make a substantial difference to your calorie intake. Fibre-rich foods can also reduce the calorie density of your meal.

3. Mindful eating: practising mindful eating involves paying attention to hunger and fullness cues, eating slowly, and avoiding distractions during meals. This approach helps prevent overeating and promotes better control over food intake.

4. Have some water: having a drink with your meal can increase satiety and reduce total food intake at a given meal. In addition, replacing sugary beverages with water has been shown to reduce calorie intake from sugars.

4. Intermittent fasting: restricting eating to specific windows can reduce your caloric intake and have positive effects on your metabolism. There are different types of intermittent fasting you can do, but one of the easiest types is restricting your mealtimes to a specific window of time (such as only eating between 12 noon and 8pm). This reduces night-time snacking, so is particularly helpful if you tend to get the snacks out late in the evening.

Long-term behavioural changes are crucial for maintaining weight loss. Successful strategies include regular physical activity, continued mindful eating, and periodically being diligent about your weight and food intake. Having a support system to help you stay on track can also play a big role in helping you maintain weight loss.

Modest weight loss of 5-10% body weight in people who are overweight or obese offers significant health benefits, including improved metabolic health and reduced risk of chronic diseases. But it can be hard to lose weight – especially given all the adaptations our body has to prevent it from happening.

Thankfully, small, sustainable changes that lead to gradual weight loss appear to be more effective in the long run, compared with more drastic lifestyle changes.

Alexandra Cremona, Lecturer, Human Nutrition and Dietetics, University of Limerick

This article is republished from The Conversation under a Creative Commons license. Read the original article.

We all want to eat healthily, especially as we reset our health goals at the start of a new year. But sometimes these plans are sabotaged by powerful cravings for sweet, salty or carb-heavy foods.

So why do you crave these foods when you’re trying to improve your diet or lose weight? And what can you do about it?

There are many reasons for craving specific foods, but let’s focus on four common ones:

1. Blood sugar crashes

Sugar is a key energy source for all animals, and its taste is one of the most basic sensory experiences. Even without specific sweet taste receptors on the tongue, a strong preference for sugar can develop, indicating a mechanism beyond taste alone.

Neurons responding to sugar are activated when sugar is delivered to the gut. This can increase appetite and make you want to consume more. Giving into cravings also drives an appetite for more sugar.

In the long term, research suggests a high-sugar diet can affect mood, digestion and inflammation in the gut.

While there’s a lot of variation between individuals, regularly eating sugary and high-carb foods can lead to rapid spikes and crashes in blood sugar levels. When your blood sugar drops, your body can respond by craving quick sources of energy, often in the form of sugar and carbs because these deliver the fastest, most easily accessible form of energy.

2. Drops in dopamine and serotonin

Certain neurotransmitters, such as dopamine, are involved in the reward and pleasure centres of the brain. Eating sugary and carb-rich foods can trigger the release of dopamine, creating a pleasurable experience and reinforcing the craving.

Serotonin, the feel-good hormone, suppresses appetite. Natural changes in serotonin can influence daily fluctuations in mood, energy levels and attention. It’s also associated with eating more carb-rich snacks in the afternoon.

Low carb diets may reduce serotonin and lower mood. However, a recent systematic review suggests little association between these diets and risk for anxiety and depression.

Compared to men, women tend to crave more carb rich foods. Feeling irritable, tired, depressed or experiencing carb cravings are part of premenstrual symptoms and could be linked to reduced serotonin levels.

3. Loss of fluids and drops in blood sugar and salt

Sometimes our bodies crave the things they’re missing, such as hydration or even salt. A low-carb diet, for example, depletes insulin levels, decreasing sodium and water retention.

Very low-carb diets, like ketogenic diets, induce “ketosis”, a metabolic state where the body switches to using fat as its primary energy source, moving away from the usual dependence on carbohydrates.

Ketosis is often associated with increased urine production, further contributing to potential fluid loss, electrolyte imbalances and salt cravings.

4. High levels of stress or emotional turmoil

Stress, boredom and emotional turmoil can lead to cravings for comfort foods. This is because stress-related hormones can impact our appetite, satiety (feeling full) and food preferences.

The stress hormone cortisol, in particular, can drive cravings for sweet comfort foods.

A 2001 study of 59 premenopausal women subjected to stress revealed that the stress led to higher calorie consumption.

A more recent study found chronic stress, when paired with high-calorie diet, increases food intake and a preference for sweet foods. This shows the importance of a healthy diet during stress to prevent weight gain.

What can you do about cravings?

Here are four tips to curb cravings:

1) don’t cut out whole food groups. Aim for a well-balanced diet and make sure you include:

• sufficient protein in your meals to help you feel full and reduce the urge to snack on sugary and carb-rich foods. Older adults should aim for 20–40g protein per meal with a particular focus on breakfast and lunch and an overall daily protein intake of at least 0.8g per kg of body weight for muscle health
• fibre-rich foods, such as vegetables and whole grains. These make you feel full and stabilise your blood sugar levels. Examples include broccoli, quinoa, brown rice, oats, beans, lentils and bran cereals. Substitute refined carbs high in sugar like processed snack bars, soft drink or baked goods for more complex ones like whole grain bread or wholewheat muffins, or nut and seed bars or energy bites made with chia seeds and oats

2) manage your stress levels. Practise stress-reduction techniques like meditation, deep breathing, or yoga to manage emotional triggers for cravings. Practising mindful eating, by eating slowly and tuning into bodily sensations, can also reduce daily calorie intake and curb cravings and stress-driven eating

3) get enough sleep. Aim for seven to eight hours of quality sleep per night, with a minimum of seven hours. Lack of sleep can disrupt hormones that regulate hunger and cravings

4) control your portions. If you decide to indulge in a treat, control your portion size to avoid overindulging.

Overcoming cravings for sugar, salt and carbs when trying to eat healthily or lose weight is undoubtedly a formidable challenge. Remember, it’s a journey, and setbacks may occur. Be patient with yourself – your success is not defined by occasional cravings but by your ability to manage and overcome them.

Hayley O’Neill, Assistant Professor, Faculty of Health Sciences and Medicine, Bond University

This article is republished from The Conversation under a Creative Commons license. Read the original article.