Benefits of probiotics

SINGAPORE — In recent years, consuming probiotics has become a popular way to boost intestinal health. Similar to the good bacteria found naturally in the human gut, probiotics help the body to function properly, said Ms Agnes Wong, a dietitian at the National Healthcare Group Polyclinics.

For instance, probiotics may be prescribed after a course of antibiotics to help re-populate the intestinal bacteria and balance the gut’s flora. Ms Wong added that probiotics can reduce the risk of infection caused by certain inflammatory bowel diseases such as ulcerative colitis and Crohn’s disease.

According to Ms Jaclyn Reutens, head dietitian and founder of Aptima Nutrition and Sports Consultants, probiotics are also commonly prescribed to individuals who are prone to traveller’s diarrhoea or who suffer from irritable bowel syndrome, constipation and diarrhoea.

“Our intestines are where all our nutrients from food get absorbed, so a healthy gut means more nutrients are absorbed and transported around our bodies,” she said.

A PROTECTIVE BARRIER

Dr Gwee Kok Ann, consultant gastroenterologist at Gleneagles Hospital, said that probiotics help to improve the digestion of certain foods, fight infection caused by harmful bacteria and also form a barrier against harmful chemicals from the food we eat.

Some of these chemicals could be hydrocarbons and amines from cancer-potential foods or short-chain fatty acids derived from the breakdown of undigested food by our gut bacteria, he said.

Beyond gut health, Ms Reutens said probiotics may also be recommended to women who are prone to yeast infections, as a particular strain of probiotics known as lactobacillus is able to keep the vagina’s pH and yeast levels in check.

Another use of probiotics, though not proven in routine use, is for the prevention of allergy disorders such as atopic dermatitis and rhinitis, said Ms Wong.

BUFFING UP NATURALLY

The two most common strains of probiotics are lactobacillus or bifidobacterium, said Ms Reutens. They are widely known to be found in yogurt and cultured milk drinks.

Besides their digestion-boosting properties, these cultured dairy products are also good sources of protein, calcium, fibre and antioxidants, she said.

According to Dr Gwee, both lactobacillus and bifidobacteria strains produce anti-inflammatory effects but they act on different pathways or inflammatory proteins, said Dr Gwee.

Those who are lactose-intolerant can find non-dairy sources of probiotics in kefir, miso and tempeh, said Ms Reutens.

Ms Wong recommends juices, soy drinks with added probiotics and yogurt smoothies as alternatives. For savoury options, Dr Gwee suggests natto, kimchi and sauerkraut.

SELECTING THE MOST SUITABLE PROBIOTICS

With the raft of probiotic products available, how does one go about choosing the right probiotic?

A high-strength probiotic doesn’t necessarily provide the best benefits. High-strength probiotics have more than 10 billion CFU (colony forming units) per dose, said Ms Reutens. Microbiologists use CFU to describe the number of active, live organisms in a laboratory sample of probiotic.

Only the viable organisms are considered to be probiotics. There is no consensus on the minimum number of micro-organisms that must be ingested to obtain a beneficial effect, said Ms Reutens.

Ms Wong agrees. Effective levels range widely, she said, depending on the probiotic strain. Some products are effective with 50 million bacterial cells, while others require more than one trillion per day.

“A product containing a higher number of live probiotics may not be better than one with fewer,” Ms Wong said.

Children are often prescribed dosages of 5 to 10 billion CFU. For adults, it is 10 to 20 billion CFU. Significant adverse effects are rare, said Ms Reutens.

“For reference, 100ml of cultured milk drinks have 5 to 10 billion CFU, while 100g of yogurt with added live strains of bacteria have 1 to 5 billion CFU,” said Ms Reutens.

Not all probiotics are created equal, said Dr Gwee. Some probiotic products may have added prebiotics. Prebiotics are indigestible sugars that act as food for the good bacteria to feed on and grow. However, prebiotics may cause diarrhoea and excessive gas production.

Probiotics prescribed by doctors have undergone stringent review and quality checks.

These include scientific research that tests the contents of the probiotics and confirms its measurable benefits, Dr Gwee said.

Probiotics sold in health food stores and on the Internet might not have undergone such stringent checks, he added.

WHO can benefit

According to Ms Reutens, probiotics can be taken by healthy adults and children to improve general health.

There are many infant and children’s food products that are supplemented with probiotics these days. However, children who are chronically ill or have compromised immunity should not take probiotics; parents should consult their paediatricians.

Pregnant and lactating women have underlying health conditions such as a low immunity, recovering from surgery, or have compromised gut integrity, consult a doctor before starting on probiotics, said Ms Wong.