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Publisher: Professor Jennie Brand-Miller, AM, PhD, FAIFST, FNSA
Editor: Philippa Sandall
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1 August 2019
GI News - August 2019
FOOD FOR THOUGHT
GOOD CARBS: THE ORIGINAL PLANT-BASED DIET
In
some quarters, carbs get an undeserved bad rap. But students of human
evolution know that dietary carbohydrates (fruits, berries and tubers)
played an instrumental role throughout our long 3-million-year journey
from a small upright walking ape (Lucy, Australopithicus afarensis) to
the tall, smooth-skinned creature with a very large brain who can
perform high level maths as well as prolonged strenuous marathons (Homo
sapiens sapiens). You could say we evolved eating the original
plant-based diet. The challenge today however, is to ensure we consume
the high-quality carbs similar to the ones our ancestors ate that are
digested at a rate that our bodies can accommodate, preventing burnout
of our insulin-producing machinery. In Food for Thought, we answer some
of the questions we are asked about the high-quality carbs we like to
call “good carbs”.
WHAT DO CARBS DO? Our brains, nervous system, red blood
cells, kidneys and muscles during exercise prefer carbs as their energy
source. Carbs also give our cells structure, form part of our genes and
play a part in the function of some proteins. Did you know that glucose
powers the growth of a healthy human fetus born with substantially more
body fat than any other primate.
WHAT ARE CARBS?
Carbohydrates are made up of carbon, hydrogen and oxygen, so you can
see where the name comes from. You may recall seeing it written up in
your high school science books as CHO. For example, the chemical formula
for glucose is C6H12O6 which stands for six carbon atoms and six water
molecules (H2O = one water molecule; six water molecules = H2O x 6).
All
plant foods contain carbs to a greater or lesser extent—fruits,
vegetables, legumes, grains and nuts—as do milk and yoghurt, but not
most cheeses (the whey is drained away so it is just protein and fat).
WHAT ARE GOOD CARBS?
These are the plant foods the natural world has provided for us: fruits
and berries, vegetables, beans, peas, lentils, seeds, nuts, and grains
and the traditional staple foods and dishes we make from them such as
noodles, pasta and grainy, seedy breads.
WHAT ABOUT MILK? Dairy
foods such as regular milk and yoghurt are good carbs too. And let’s
not forget mother’s milk which provides the perfect mix of carbs, fat,
protein, vitamins and minerals for our babies to grow and thrive for the
first six months of life. Mother Nature made it sweet so it is very
appealing to babies. The sweetness comes from a special sugar called
lactose only found in milk. Human milk has one of the highest
concentrations of lactose of any mammal coming in at around 7 grams of
lactose per 100 millilitres (3½ fluid ounces) which in household
measures is little over ⅓ cup. It contains almost 50% more than that of
cow’s milk. Why so much? One reason is probably to satisfy our
fast-growing, energy-hungry, glucose-demanding brain. Scans show that a
baby’s brain reaches more than half adult size in the first 90 days of
baby’s life. Mother’s milk also contains special carbs called
oligosaccharides (think of them as prebiotics), which friendly bacteria
in the large intestine chomp on to thrive.
WHAT’S SO GOOD ABOUT GOOD CARBS? They
are sustaining and sustainable foods that come with a swag of
micronutrients we need for good health including vitamins B, C and E;
minerals such as magnesium, potassium and calcium and antioxidants
including the carotenoids that play a protective role in eye health. Dan
Buettner’s Blue Zones studies provide compelling evidence that dietary
patterns that are rich in good carbs and dietary fibre reduce the risk
of weight gain, type 2 diabetes, coronary heart disease and certain
kinds of cancer, like colorectal cancer.
HOW MUCH CARBOHYDRATE DO WE NEED?
Our diet is not limited to One Size Fits All. You only have to look
around the world to see that there are very different dietary patterns
with very different fuel mixes associated with good health and long
life. Traditional Mediterranean and Japanese diets which are both linked
with a long and healthy life couldn’t be more different. The
Mediterranean diet is relatively high in fats and tends to be rather
moderate in carbs. The Japanese diet, like most Asian diets, is high in
carbs and low in fats. What they have in common and what seems to matter
most is that they are based on good, wholesome foods and ingredients.
Mostly plants.
WHAT ABOUT BLOOD GLUCOSE? When we
eat carb-rich foods, our bodies convert their sugars and/or starches
into glucose during digestion. However, our bodies do this at very
different rates and this is where using the glycemic index (GI) helps us
make better choices for long-term health and wellbeing. The GI is
particularly useful for people who need to manage their blood glucose
levels (BGLs). Think of it as a carbo speedo that gives us an idea how
quickly our bodies will digest particular carb foods and how fast and
high our BGL is then likely to rise.
Research around
the world over the past forty years shows that switching to eating
mainly low GI carbs throughout the day that will trickle glucose into
our bloodstream and lower our day-long blood glucose and insulin levels
helping us:
- Manage our appetite because we will feel fuller for longer
- Minimise our body fat
- Maximise our muscle mass
- Decrease our risk of type 2 diabetes and heart disease.
Read More:
WHAT’S NEW?
THE HUMBLE GLYCEMIC INDEX MARKS GLOBAL DIABETES RISK
ConscienHealth’s
Ted Kyle reports on a systematic review and meta-analysis of glycemic
index, glycemic load, and type 2 diabetes risk published in Nutrients by
an impressive global group of nutrition scientists. Their conclusions
are simple and powerful he says. Glycemic index and glycemic load are
important markers of food quality. In fact they do an excellent job of
predicting type 2 diabetes risk for individuals and for the population.
Almost 40 years ago, David Jenkins published the first paper to
propose that the glycemic index of foods might be an important measure
of nutrition quality. Back then, dietary guidance pointed to a low-fat
panacea. Research continued quietly on the glycemic index. The pendulum
swung from fear of fats to carbophobia. Sugar is the villain of the day
now. But maybe the time has come for the glycemic index to bring a bit
more objectivity.
Perhaps some of the energy that goes
into vilifying carbs, sugar, soda, and other dietary goblins would be
better spent directing people toward better carbs. “Don’t” has never
been an especially effective tool for behavior modification.
Senior
author on this new paper, Jennie Brand-Miller, explains the appeal of
the glycemic index: “I liked the fact that it turned traditional
nutritional science upside down. The old wisdoms were that sugars were
bad and starches were good, but the GI showed some starches, such as
potatoes, converted to glucose far quicker than some sugars. What
appealed most was that GI intuitively made sense. We all talk about
needing a sugar hit or having a sugar low, and this provided an
explanation. It provided a way in to explore how foods can affect not
just our physical health, but our moods as well.”
And
now we know that glycemic index is a good marker for how changes in the
food supply are driving an increased type 2 diabetes risk. Maybe now we
can move from the narrow focus on macronutrients to a broader view of
dietary quality. It looks like paying attention to this humble index
might help.
Read more:
WHAT’S HOT?
PLANT-BASED BURGERS
A
recent post in Refinery29 (“a modern woman's destination for how to
live a stylish, well-rounded life”) says “grilling up a good time
doesn't have to mean meat-based burgers for all. In fact, these days
there are a lot of meatless burger alternatives on the market. From
veggie and plant protein patties to quinoa and bean-based, non-meat
eaters have plenty of options when it comes to grilling out.” Their
reporter found that some people looked for trad veggie burgers, while
others want burgers to taste as much like real meat as possible.
Meat substitutes are certainly having a moment in the sun.
Writing for the New York Times, Timothy Egan says “fake meat will save
us.”
PR like that is an agency’s dream come true says
ConscienHealth’s Ted Kyle. So, it’s no wonder that Beyond Meat was
“going bananas” with a 550 percent surge in its stock price after a very
successful IPO. Its rival, Impossible Foods, can’t keep up with demand
for its Impossible Burger. That’s good news for farmers who can’t sell
their soybeans – a typical plant-based protein source. Suddenly, pea
protein is hot. Prices for this humble legume are rising, even though
soybean prices are depressed. The biggest meat processor in the U.S.,
Tyson Foods, is jumping in to build a billion-dollar brand with
half-pea, half-beef burgers. Kellogg is supposedly sitting on a goldmine
with its Morningstar Farms brand for fake meat.
Kyle
asks if PR spin is tapping into foodie moralism to make this highly
processed food seem like a healthy choice? Yes, indeed, he says. We need
to move toward a more sustainable diet that won’t destroy the planet he
says. Fake burgers, though? It’s unlikely they’ll give us a healthier
diet. Maybe it’s time to remind ourselves of Michael Pollan’s top tip:
“Eat food, not too much, mostly plants.” By food Pollan means fruit,
vegetables, fruits, legumes, whole grains, nuts and seeds, seafood,
poultry and meat and to avoid what he calls “edible food-like
substances.”
Read more:
PRODUCT REVIEW
BURGERS
Since
everyone seems to be talking (and eating) burgers, we thought it would
be interesting to compare a regular lean beef patty that just contains
lean beef, with a meatless patty (we chose the top-seller Beyond Meat
Beyond Burger™) and a homemade chickpea patty (the recipe is from The Low GI Vegetarian Cookbook). The nutrition information here is for the patty alone.
LEAN BEEF PATTY
Ingredients: Lean minced beef.
BEYOND MEAT BEYOND BURGER
Ingredients:
Water, Pea Protein Isolate*, Expeller-Pressed Canola Oil, Refined
Coconut Oil, Rice Protein, Natural Flavors, Cocoa Butter, Mung Bean
Protein, Methylcellulose, Potato Starch, Apple Extract, Salt, Potassium
Chloride, Vinegar, Lemon Juice Concentrate, Sunflower Lecithin,
Pomegranate Fruit Powder, Beet Juice Extract (for color).
(*Peas
are legumes. People with severe allergies to legumes like peanuts
should be cautious when introducing pea protein into their diet because
of the possibility of a pea allergy. Our products do not contain peanuts
or tree nuts.)
CHICKPEA PATTY
Ingredients: 400g
(14oz) can chickpeas, rinsed and drained, 1½ tablespoons olive oil, 1
onion, finely chopped, 1 garlic clove, crushed, 1 tablespoon mild Indian
curry paste, 1 zucchini, grated, 110g (4oz/1½ cups) firmly packed fresh
wholegrain breadcrumbs, 1 tablespoon freshly chopped coriander, 1 egg,
lightly beaten, Wholemeal plain flour, to dust. Serves 4.
Read more:
PERSPECTIVES WITH DR ALAN BARCLAY
LOW CARB?
Low carb diets are still very popular in many
parts of the world. The problem is, many people do not seem to really
understand what “carbs” actually are. Consumer research in Europe, for
example, has found that only 51% of consumers can correctly identify a
carbohydrate. This is not really surprising, because carbohydrates are
complicated and not currently well described on food labels.
CARBS IN FOODS Carbohydrates include varieties that are digestible by humans (known scientifically as available carbohydrates):
- Oligosaccharides (e.g., maltodextrins)
- Starches (e.g., amylose and amylopectin)
- Sugars (e.g., fructose, galactose, glucose, lactose, maltose and sucrose)
- Dietary fibres (e.g., cellulose, gums, hemicellulose, mucilages and pectins)
- Fruits
- Grains (e.g., barley, oats, rice, rye, wheat, etc.)
- Legumes (e.g., peas, beans, lentils, chickpeas, etc.)
- Milk
- Nuts
- Seeds
- Vegetables
- Yoghurt
- Flours (e.g., plain wheat flour)
- Sugars (e.g., table sugar, or sucrose)
- Dietary fibres (e.g., pectin)
North Americans are provided with more information – Nutrition Facts panels must include:
- Total carbohydrate
- Dietary fiber
- Total sugars
- Added sugars
WHAT DOES “LOW CARB” MEAN? Many people that are following low carb diets today are in reality following low starch diets that primarily exclude or limit grains (e.g., breakfast cereals, breads, pastas, rice, etc...) and starchy vegetables (e.g., corn, potatoes, peas, etc...). Most aren’t specifically aiming to exclude dietary fibre, although a reduced fibre intake is often an unwanted side-effect.
Even the definition of a low carb diet is hotly debated. One of the more popular systems classifies diets according to the amount of total available carbohydrate they provide:
- Very low-carbohydrate diet. 20–50 grams per day or less than 10% of a 2000 Calorie (8,400 kJ diet)
- Low carbohydrate diet. Less than 130 grams per day or less than 26% of energy from a 2000 Calorie (8,400 kJ diet)
- Moderate carbohydrate diet. 130–230 grams per day, or 26–45% of energy from a 2000 Calorie (8,400 kJ diet)
- High carbohydrate diet. More than 230 grams per day or more than 45% of energy from a 2000 Calorie (8,400 kJ diet)
HOW MUCH CARBOHYDRATE ARE WE EATING? Many people in the developed world could be forgiven for thinking that our diets are high in carbohydrate, and should reduce our intakes. However, we know from the latest Australian Health Survey that on average, Australian adults consumed an average of 222 grams of carbohydrate per day in 2011–12, or 44% of energy from carbohydrates, putting them in the moderate carbohydrate diet camp.
ENJOY GOOD CARBS Most people in the developed world don’t need to consume a low carbohydrate diet. Enjoying a traditional dietary pattern with a long history of health, well-being and longevity, like the traditional Mediterranean diet or Japanese diet, is a better strategy – and both diets contain plenty of fruit and vegetables, something most people don’t eat enough of.
Read more:
- Literature review on consumer knowledge, attitudes and behaviours relating to sugars and food labelling
- Australian Health Survey: Nutrition First Results - Foods and Nutrients, 2011-12
Alan Barclay, PhD is a consultant dietitian and chef (Cert III). He worked for Diabetes Australia (NSW) from 1998–2014 . He is author/co-author of more than 30 scientific publications, and author/co-author of The good Carbs Cookbook (Murdoch Books), Reversing Diabetes (Murdoch Books), The Low GI Diet: Managing Type 2 Diabetes (Hachette Australia) and The Ultimate Guide to Sugars and Sweeteners (The Experiment, New York).
Contact: You can follow him on Twitter or check out his website.
GOOD CARBS FOOD FACTS
SWEET CORN
It’s hard to beat the juicy burst of sweet corn
kernels straight from the cob. Peel back the husk of a fresh ear of corn
(stripping away the silk) and we are munching through the neat rows of
yellow or white kernels of a very big grass seed head that was
cultivated in the Americas for thousands of years before Christopher
Columbus arrived on the scene.
Although “officially” a grain, the particular variety we tuck
into is very much eaten immature as a vegetable. Boil, steam, microwave,
bake or barbecue and serve piping hot with just a dot of butter and
sprinkle of salt. Or add the kernels to soups, stews and stir fries;
fritters and frittatas; chowders and crepes; salsas and salads; muffins,
breads and corn cakes, and toss whole baby corn into stir-fries.
Buy
cobs with fresh green unblemished husks that fit snugly with moist
slightly brown silky tassels intact. (If the tassels are black or dry,
the corn is old: if dry and pale the corn is immature) if you can get a
peek at the kernels, they should be tightly packed, plump, shiny and
smaller at the tip than they are in the middle (this indicates a young
cob). When sweet corn is really fresh, the kernels will release a milky
liquid when cut. As the natural sugars in the kernels start converting
to starch once the husk is removed, resist buying pre-packed shucked
ears. Snap-frozen cobs and kernels make a handy year-round substitute.
Wholegrain products made from corn include:
- Polenta, a coarsely ground dried corn that is actually a type of grits. (Avoid instant polenta, it may be convenient and foolproof but it’s not the same at all.)
- Corn grits, which are chopped up dried kernels that you can use in soups or stews or serve as a side dish.
- Hominy grits are corn grits that have been treated with an alkaline solution (nixtamalized).
Source:
THE GOOD CARBS KITCHEN
It’s all about corn this month with Barbecued Corn with Avocado Cream from Dr Alan Barclay’s book, Reversing Diabetes; Chicken and Corn Soup with Toasted Tortilla and Avocado from The Good Carbs Cookbook; and for the kids, Diane Temple’s Chicken and Corn Nuggets from the Money Saving Meals series we ran in 2010.
BARBECUED CORN WITH AVOCADO CREAM
The avocado cream can also be used as a creamy topping for jacket potatoes
or as a spread for toast or sandwiches says Alan Barclay. It’s full of
healthy unsaturated fats, dietary fibre and potassium.
Serves 2 • Preparation 5 minutes + 15 minutes soaking • Cooking 20 minutes
2 corn cobs, husks attached
1 long red chilli, finely chopped
lime cheeks, to serve
For the avocado cream
1 small avocado
1 tablespoon lime juice
¼ tsp cayenne pepper
tablespoon coriander (cilantro) leaves, finely chopped
Peel
back the husks from the corn cobs, discard the silk and remove several
of the inside husks, leaving a few outer husks to protect and steam the
corn while it is cooking. Soak the corn cobs and two pieces of string in
a large bowl of water for 15 minutes. • Meanwhile, to make the avocado
cream, use a stick blender or small food processor to blend the avocado,
lime juice and cayenne pepper until it reaches a smooth, spreadable
consistency. Stir in the coriander and set aside until needed. • Preheat
a barbecue or chargrill pan to medium–high. Drain the corn cobs, reseal
the husks and secure with the wet string. Cook the corn, turning
occasionally, for 15–20 minutes or until tender. • Peel back the husks
and spread the corn with the avocado cream. Sprinkle with the chilli and
serve with lime cheeks.
Per serving
Energy
1790kJ/426 calories; Protein 9g; Fat 29g (includes 6g saturated fat;
saturated : unsaturated fat ratio 0.26); Carbohydrate 27g (includes 4g
sugars and 23g starches); Fibre 9g; Sodium 9mg; Potassium 1475mg; sodium
: potassium ratio 0.01
CHICKEN AND CORN SOUP WITH TOASTED TORTILLA AND AVOCADO
Much of the depth of flavour in this soup comes from the first step of
gently cooking the veggies in oil says Kate McGhie. Once there’s a
slight sizzle, put the lid on the pan to keep the aromatic moisture in
while the veggies soften. Her top tip? Cook the chicken the day before
and use the stock for the soup. • Preparation time: 25 minutes • Cooking
time: 25 minutes • Serves: 8
2 tablespoons olive oil
1 medium onion, finely chopped
2 garlic cloves, crushed
1 medium zucchini, finely diced
1 medium carrot, finely diced
2½ litres chicken broth
400g (14oz) can chick peas, rinsed
Salt flakes
2 medium (about 320g) boneless, skinless chicken breasts, poached
1 small red chilli, finely chopped
2 handfuls coriander (cilantro) leaves, coarsely chopped
3 large tortillas
1 medium avocado, sliced
1 small lime, cut into thin wedges
Put the oil in a large pot and when hot add the onion, garlic, zucchini and
carrot. Cook gently until the vegetables soften and then add the
chicken stock, chick peas and salt to taste. Cover and simmer for 15
minutes. • Shred the chicken and stir through the hot soup with the
chilli and half of the coriander. • Lightly toast the torillas and cut
into fine strips. • Ladle the soup into bowls, garnish with a few
avocado slices, some tortilla strips, remaining coriander and serve with
lime wedges for squeezing over the soup.
Per serving
Energy 1540kJ/370 calories; Protein 26g; Fat 19g (includes 4g saturated fat;
saturated : unsaturated fat ratio 0.3); Carbohydrate 21g (includes 4g
sugars and 17g starches); Fibre 7g; Sodium 1030mg; Potassium 695mg;
sodium : potassium ratio 1.48
CHICKEN AND CORN NUGGETS
The next time the clamour for takeaway starts, try these lightly pan-fried
nuggets for a quick and easy, budget friendly meal instead. You can also
bake them, but they’ll take a little longer to cook. The nuggets also
double as tasty finger food when entertaining and leftovers (if there
are any) are ideal for lunch boxes says Diane Temple. Makes about 30
500g (1lb 2oz) chicken mince
1 tablespoon soy sauce
2 cloves garlic, crushed
125g (4oz) can corn kernels, drained
1 cup fresh breadcrumbs made from grainy bread
2 tablespoons chopped chives
½ cup panko crumbs
2 tablespoons canola oil
To serve
Celery and carrot sticks
Tiny tomatoes
Blanched snowpeas (mangetout) or sugar snap peas
Crispy green beans
Tomato, barbecue or sweet chilli sauce
Mix
the chicken mince, soy sauce, garlic, corn kernels, fresh breadcrumbs
and chives together. With damp hands, roll 1 tablespoon of the mixture
into a ball, then flatten it slightly. Repeat with the rest of the
mixture. Roll each nugget in dry breadcrumbs and chill in the fridge for
10–20 minutes. • Heat the oil in a large non-stick frying pan and cook
the nuggets in batches (about 2 minutes each side) until golden brown
and cooked through. Place them on a tray lined with paper towel. Repeat
with remaining nuggets.
Per nugget
Energy: 236kJ/ 56 calories; Protein 4g; Fat 4g (includes 0.5g saturated fat, saturated :
unsaturated fat ratio 0.1); Carbohydrate 3g; Fibre 9g
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