Research over the years has suggested intermittent fasting has the potential to improve our health and reduce the likelihood of developing cancer.

So what should we make of a new study in mice suggesting fasting increases the risk of cancer?

What is intermittent fasting?

Intermittent fasting means switching between times of eating and not eating. Unlike traditional diets that focus on what to eat, this approach focuses on when to eat.

There are lots of commonly used intermittent fasting schedules. The 16/8 plan means you only eat within an eight-hour window, then fast for the remaining 16 hours. Another popular option is the 5:2 diet, where you eat normally for five days then restrict calories for two days.

In Australia, poor diet contributes to 7% of all cases of disease, including coronary heart disease, stroke, type 2 diabetes, and cancers of the bowel and lung. Globally, poor diet is linked to 22% of deaths in adults over the age of 25.

Intermittent fasting has gained a lot of attention in recent years for its potential health benefits. Fasting influences metabolism, which is how your body processes food and energy. It can affect how the body absorbs nutrients from food and burns energy from sugar and fat.

What did the new study find?

The new study, published in Nature, found when mice ate again after fasting, their gut stem cells, which help repair the intestine, became more active. The stem cells were better at regenerating compared with those of mice who were either totally fasting or eating normally.

This suggests the body might be better at healing itself when eating after fasting.

However, this could also have a downside. If there are genetic mutations present, the burst of stem cell-driven regeneration after eating again might make it easier for cancer to develop.

Polyamines – small molecules important for cell growth – drive this regeneration after refeeding. These polyamines can be produced by the body, influenced by diet, or come from gut bacteria.

The findings suggest that while fasting and refeeding can improve stem cell function and regeneration, there might be a tradeoff with an increased risk of cancer, especially if fasting and refeeding cycles are repeated over time.

While this has been shown in mice, the link between intermittent fasting and cancer risk in humans is more complicated and not yet fully understood.

What has other research found?

Studies in animals have found intermittent fasting can help with weight loss, improve blood pressure and blood sugar levels, and subsequently reduce the risks of diabetes and heart disease.

Research in humans suggests intermittent fasting can reduce body weight, improve metabolic health, reduce inflammation, and enhance cellular repair processes, which remove damaged cells that could potentially turn cancerous.

However, other studies warn that the benefits of intermittent fasting are the same as what can be achieved through calorie restriction, and that there isn’t enough evidence to confirm it reduces cancer risk in humans.

What about in people with cancer?

In studies of people who have cancer, fasting has been reported to protect against the side effects of chemotherapy and improve the effectiveness of cancer treatments, while decreasing damage to healthy cells.

Prolonged fasting in some patients who have cancer has been shown to be safe and may potentially be able to decrease tumour growth.

On the other hand, some experts advise caution. Studies in mice show intermittent fasting could weaken the immune system and make the body less able to fight infection, potentially leading to worse health outcomes in people who are unwell. However, there is currently no evidence that fasting increases the risk of bacterial infections in humans.

So is it OK to try intermittent fasting?

The current view on intermittent fasting is that it can be beneficial, but experts agree more research is needed. Short-term benefits such as weight loss and better overall health are well supported. But we don’t fully understand the long-term effects, especially when it comes to cancer risk and other immune-related issues.

Since there are many different methods of intermittent fasting and people react to them differently, it’s hard to give advice that works for everyone. And because most people who participated in the studies were overweight, or had diabetes or other health problems, we don’t know how the results apply to the broader population.

For healthy people, intermittent fasting is generally considered safe. But it’s not suitable for everyone, particularly those with certain medical conditions, pregnant or breastfeeding women, and people with a history of eating disorders. So consult your health-care provider before starting any fasting program.

Amali Cooray, PhD Candidate in Genetic Engineering and Cancer, WEHI (Walter and Eliza Hall Institute of Medical Research)

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

Cranberry juice has been used medicinally for centuries. Our new research indicates it should be a normal aspect of urinary tract infection (UTI) management today.

While some benefits of cranberry compounds for the prevention of UTIs have been suspected for some time, it hasn’t been clear whether the benefits from cranberry juice were simply from drinking more fluid, or something in the fruit itself.

For our study, published this week, we combined and collectively assessed 3,091 participants across more than 20 clinical trials.

Our analysis indicates that increasing liquids reduces the rate of UTIs compared with no treatment, but cranberry in liquid form is even better at reducing UTIs and antibiotic use.

Are UTIs really that bad?

Urinary tract infections affect more than 50% of women and 20% of men in their lifetime.

Most commonly, UTIs are caused from the bug called Escherichia coli (E.coli). This bug lives harmlessly in our intestines, but can cause infection in the urinary tract. This is why, particularly for women, it is recommended people wipe from front to back after using the toilet.

An untreated UTI can move up to the kidneys and cause even more serious illness.

Even when not managing infection, many people are anxious about contracting a UTI. Sexually active women, pregnant women and older women may all be at increased risk.

Why cranberries?

To cause a UTI, the bacteria need to attach to the wall of the urinary bladder. Increasing fluids helps to flush out bacteria before it attaches (or makes its way up into the bladder).

Some beneficial compounds in cranberry, such as proanthocyanidins (also called condensed tannins), prevent the bacteria from attaching to the wall itself.

While there are treatments, over 90% of the bugs that cause UTIs exhibit some form of microbial resistance. This suggests that they are rapidly changing and some cases of UTI might be left untreatable.

What we found

Our analysis showed a 54% lower rate of UTIs from cranberry juice consumption compared to no treatment. This means that significantly fewer participants who regularly consumed cranberry juice (most commonly around 200 millilitres each day) reported having a UTI during the periods assessed in the studies we analysed.

Cranberry juice was also linked to a 49% lower rate of antibiotic use than placebo liquid and a 59% lower rate than no treatment, based on analysis of indirect and direct effects across six studies. The use of cranberry compounds, whether in drinks or tablet form, also reduced the prevalence of symptoms associated with UTIs.

While some studies we included presented conflicts of interest (such as receiving funding from cranberry companies), we took this “high risk of bias” into account when analysing the data.

So, when can cranberry juice help?

We found three main benefits of cranberry juice for UTIs.

1. Reduced rates of infections

Increasing fluids (for example, drinking more water) reduced the prevalence of UTIs, and taking cranberry compounds (such as tablets) was also beneficial. But the most benefits were identified from increasing fluids and taking cranberry compounds at the same time, such as with cranberry juice.

2. Reduced use of antibiotics

The data shows cranberry juice lowers the need to use antibiotics by 59%. This was identified as fewer participants in randomised cranberry juice groups required antibiotics.

Increasing fluid intake also helped reduce antibiotic use (by 25%). But this was not as useful as increasing fluids at the same time as using cranberry compounds.

Cranberry compounds alone (such as tablets without associated increases in fluid intake) did not affect antibiotic use.

3. Reducing symptoms

Taking cranberry compounds (in any form, liquid or tablet) reduced the symptoms of UTIs, as measured in the overall data, by more than five times.

Take home advice

While cranberry juice cannot treat a UTI, it can certainly be part of UTI management.

If you suspect that you have a UTI, see your GP as soon as possible.

Christian Moro, Associate Professor of Science & Medicine, Bond University and Charlotte Phelps, Senior Teaching Fellow, Medical Program, Bond University

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