Prebiotic, probiotic and synbiotic: who’s who?

A few definitions

Probiotics are « live microorganisms which when administered in adequate amounts confer a health benefit on the host », according to the FAO.
Probiotics supplements and additives contain a single or a mix of strains, the most commonly used being lactobacilles.

Prebiotics are nutrients that are degraded by gut microbiota. They feed the intestinal microbiota, and their degradation products are short-chain fatty acids that are released into blood circulation, consequently, affecting not only the gastrointestinal tracts but also distant organs.
Prebiotics are mostly fibers (for example inulin, pectin), which stimulate the growth and/or activity of gut bacteria. Prebiotics are present in natural products, but they may also be added to food.

Put simply, probiotics are live bacteria, and prebiotics are their preferred food.

Synbiotics are synergistic combinations of pro- and prebiotics.

What is the mechanism of action of probiotics and probiotics ?

Firstly, by promoting the growth of gut bacteria, probiotics contribute to the normal function of the organism. This effect is interesting to restore the microbiote after an antibiotic therapy. Secondly, probiotics could inhibit the development of pathogenic bacteria responsible for food poisoning.
Probiotics microorganisms not only naturally produce B group vitamins, they improve the absorption of other vitamin and mineral compounds and contribute to proper immune function.
Eventually, probiotics may be able to produce enzymes and show antibiotic, anti-cancerogenic, and immunosuppressive properties.

Prebiotics affect the composition of the intestinal microbiota and its metabolic activity. By doing so, they modulate lipid metabolism and the immune system, increase calcium absorption, and impact the bowel function, which confers a health benefit on the host.

Probiotics are essentially active in the small and large intestine, while the effect of prebiotics is observed mainly in the large intestine. Associating selected probiotics and prebiotics in the form of synbiotics may therefore enhance these effects.

Health benefits

Probiotics, probiotics and synbiotics have systemic effects on the host’s health metabolism and immune system. A recent review presents some of these benefits, which I list here.

  • increased satiety, which could help weight loss
  • anti-inflammatory and modulation of the immune system
  • increased absorption of minerals (bioavailability)
  • regulation of transit
  • improved gut health
  • prevention of cardio-vascular diseases

Food products rich in prebiotics and probiotics

Prebiotics are naturally occurring in fibre-rich foods such as: artichoke, asparagus, jerusalem artichoke, garlic, onion, leek, oats, kiwis, citrus fruits.

Probiotics are found in fermented foods such as: yogurt, kefir, kombucha, sauerkraut, pickles, miso, tempeh, kimchi, sourdough bread and blue cheeses.

In season: April

Spring is finally here! A weird Spring for sure, for many of us are quarantined because of coronavirus. While we are social distancing, nature is bursting and brings delicious fruit and vegetables to our table.

Sourcing fresh fruit and vegetables can be tricky these days. Remember that tinned and frozen are valid alternatives. Frozen and tinned fruit and veg can be cheaper than fresh, they are usually picked at when they are full-grown and mature meaning a higher content in micronutrients.

To finish, please shop sensibly: do not stockpile yet do not go out too often, and rinse your fresh fruit and veg carefully.

Fruits

Apples and pears are still in season in April, so are kiwis, oranges, pomelo, lemons and limes. You may find the first local varieties of strawberries in your shop as well as rhubarb. Ideal to bake a pie or crumble!

Vegetables

As you can see above, caulis and cabbage, beetroots are still in season. Versatile cucumber and carrots too, and you may find the first asparagus. Leafy greens such as lettuce and spinach are a good means to add vitamins and minerals to your plate.

Whether you have them fresh, tinned or frozen, enjoy your fruit and veg!

In season: February

Some of us may start to feel bored with winter food (me!), but look, the days are getting longer and here and there hide the first signs of Spring.
Plus, February is the peak season for delicious fruits and vegetables!

seasonal fruit veg february
http://angelgreens.co.uk/

Vegetables

Brussel sprouts, cauliflower, celeriac, kale, leeks, parsnips, potatoes, shallots, swedes, turnips, wild mushrooms, cabbage, winter squash…

End of season: beetroot and celery

Beginning of season: rhubarb

Fruits

Apples, pears, clementines, lemon, oranges, kiwis, passion fruit, pomegranate

Fish and seafood

Haddock, mussels, oysters, salmon

Find out more

Angel Green is a not-for-profit social enterprise, providing organic vegetables directly from local farms to Islington and King’s Cross residents and those working in the area.

Portion sizes and food groups – adults

Most of us don’t measure portion sizes when we eat, we serve ourselves according to our appetite, liking or disliking of available food, time, servings of ready made meals etc. That’s absolutely fine, and I certainly don’t support weighing food or counting calories, however I believe that a refresh of portion sizes of each food group could be a helpful reminder for all of us.

Remember that having a healthy diet is a matter of balance over a week, not a meal.

Vegetables and Fruits

Yes, I put vegetables first because they are packed with so many nutrients and are so versatile, I am a big fan. Anyway, both vegetables and fruits are amazing sources of vitamins, minerals and dietary fibres, which I will detail in another article. Meanwhile this paper gives you a precise idea of the health benefits.

The common recommendation is to have at least 5 portions of fruit and vegetables per day, preferably at least 3 veg and 2 fruits. However a recent study by Imperial College concluded that the more of you have, the better: the health effects of fruit and veg were greater with an intake of at least 10 portions per day!

Aim at a third to half of your meal/diet made up by fruit and vegetables.

Carbohydrates

Carbohydrates are found in starchy foods like potatoes (which don’t count as veg), cereals (wheat, oats, buckwheat, tapioca…), rice. It is important to vary the sources of carbohydrates as they don’t provide the same amino acids: try wheat, corn or buckwheat pasta, rice in various forms and varieties, rye bread etc.

Carbohydrates should account for roughly a third of your diet. They provide energy, proteins, fibres when you choose them wholegrain.

A typical serving of raw/uncooked as a main is a handful to a palm of pasta (80-100g), a handful of rice (50-60g), 3 tablespoons of breakfast cereals (30-40g).

Tip: weigh your breakfast cereal serving once for all in your breakfast bowl, make a mental note of it and never think about it again. Likewise you can weigh your or your family’s serving of raw pasta/rice/quinoa, visualise it in a plate/serving dish/your hand.

Free-sugar are carbohydrates, they provide energy and no other nutrients. Adults should have no more than 30g of free sugars a day (roughly 7 sugar cubes)

Proteins

Proteins come from animal or plant food. We only need 0.5 to 0.8g of protein per kilo each day, for a 70g adult this is 35 to 56g per day. Actually, with our Western diets, it is almost impossible not to meet our daily requirements for proteins, even if you are vegetarian or vegan.

For example, a 100g serving of raw pasta will provide you with 5g of proteins, 2 eggs with 12g, a serving of lentils (50g raw) is 5g etc. Over a day, it quickly adds up to 40-50g of proteins!

Portion sizes can be estimated as follows:
animal proteins: meat: one portion of meat = a deck of cards, fish = palm of hand, 2 eggs
plant proteins: 4 tablespoons of lentils/beans/meat alternative

Dairy and dairy alternatives

There is a growing (and interesting) controversy on dairy products, which I will not tackle here. Dairy and dairy alternative provide fats, proteins, minerals such as calcium, phosphorus and iodine and vitamins such as A, D, B2, B12.

A typical portion of dairy drink is a glass (200ml), a pot for yogurt (125g), and for cheese a matchbox (30g).

Fats

Fats are essential in a balanced diet, our cells membrane is made of fat and cholesterol, so are some hormones, our brain etc. They are vectors for fat soluble vitamins A, D, E.

Fats are found in most protein foods and added when cooking or serving. The NHS recommends to keep the total daily fat intake under 70g for adults.

Oily fish (trout, salmon, mackerel, sardines ) provide essential fatty acids, the omega-3. It is recommended to have at least 1 portion = palm of hand of oily fish per week.
Likewise, nuts provide mono-unsaturated fats food for your heart, and omega-6. One portion = half a handful per day is advisable.

Generally speaking, one portion of fat (oil, butter, spread) is a fingertip = a teaspoon = 5g.

Avoid trans-fat, prefer healthier and stable fats for cooking such as olive oil and butter.