Healthy Living, Nutrition

Red meat and cancer

You may have noticed that there’s been a fair bit in the news lately about how eating lots of red and processed meat causes cancer. This latest media frenzy was caused after the International Agency for Research on Cancer (IARC) released a report in October stating that processed meat is a ‘definite’ cause of cancer, and red meat a ‘probable’ cause.

What are red and processed meats?
Red meat refers to all mammalian muscle meat, including, beef, veal, pork, lamb, mutton, horse, and goat. Note that this list includes pork, and minced meat would also come under this classification.
Processed meats include any meat that has been salted, cured, smoked or other processes used to enhance flavour or preserve. For example; bacon, salami, sausages, ham and canned meats.

What did the IARC report investigate?
Actually, this report didn’t investigate anything new, it was an evaluation of existing evidence and research. They evaluated over 800 studies that involved the relationship between intake of red and processed meats and cancer. According to this evidence, they then worked on grouping foods into certain classifications.
(An important thing to note is that the categories in the infogram below represent how confident the IARC are that something causes cancer, not how much cancer it causes).

151026-IARC-Meat-rating-TWITTER

Basically, what this chart is telling us, is that the IARC found sufficient evidence to conclude that high intakes of processed meats definitely cause cancer. The evidence for red meats was not as strong or clear, so is classified as a ‘probable’ cause of cancer.
Most of the evidence was linked to bowel (colorectal) cancer, and stems from a meta-analysis of 10 studies published in 2011. A key finding from this paper was that processed meat was more strongly linked to bowel cancer than red meat. They concluded that:
Every 50g/day of processed meat increases the risk of colorectal cancer by 18%.
Every 100g/day of red meat increases the risk of colorectal cancer by 17%.

However, this doesn’t mean that eating red or processed meats increases your risk of bowel cancer by 17/18%, as this is a measure of relative risk. In other words, someone who eats 50g of processed meat every day has a 1.18 times increased risk of developing bowel cancer when compared to someone who doesn’t eat processed meat. To put this into perspective, compare it with smoking (the most important avoidable cause of cancer in the world). Men who smoke 15-24 cigarettes a day have a 26 times higher risk of developing lung cancer than non-smokers.

So should I still eat red meat?
Red meat is fine in moderation, and is a valuable source nutrients including protein, iron and zinc. But, what exactly is moderation? This is much harder to quantify.
In general, the Department of Health recommends that people who eat more than 90g (cooked weight) of red meat per day should cut down to 70g or less. Try to keep processed meats such as sausages and salami as ‘occasional’ foods rather than things you eat every day. You could also try having alternative sources of protein such as chicken, turkey, fish, lentils and pulses (kidney beans, chickpeas etc.)

In conclusion, having a diet that is high in red meat is not good for you, but the occasional bacon sandwich is still fine. And importantly, the risks are much lower than other things associated with cancer risk, such as smoking.

More info:
IARC Press release
IARC FAQs

Cancer Research, UK: Processed meat and cancer
NHS Choices: Red meat and bowel cancer
Cancer Research, UK: Smoking and lung cancer

Healthy Living, Nutrition, Weight Loss

Fibre

Dietitians and other healthcare professionals can often be heard talking about how we should eat more fibre. You may understand that it is “good for you” to have fibre in your diet. But have you ever thought about why?

This post explains the different types of fibre, looks at some of its benefits and suggests how you can include more of it in your diet.

Types of fibre

Fibre-rich foodsAn easy way to remember foods that contain fibre is that they all come from plants. Meat, fish and dairy foods do not contain fibre.
Fibre can be split into two different types, soluble and insoluble. Both have different health benefits, so we should try to include both types in our diets.

  • Soluble fibre
    As the name suggests, soluble fibre dissolves in water. In the gut, this helps soften your stools. Consequently, if you suffer from constipation, gradually increasing your intake of soluble fibre can help make it easier to go. Soluble fibre can also help lower cholesterol levels.
    Foods such as oats, pulses, lentils, golden linseeds, potatoes and vegetables are all good sources of soluble fibre.
  • Insoluble fibre
    Insoluble fibre cannot be digested, instead it is used as a ‘food’ source for good bacteria we have in the gut, helping keep our gut healthy. Insoluble fibre also acts as a sponge, helping keep us fuller for longer and move food through our digestive system.
    Good sources of insoluble fibre include; bran, wholegrain and wholemeal foods, skins of fruits and vegetables and nuts and seeds.

To help differentiate between the two different types, think about making porridge (or oatmeal) on the stove, the oats ‘dissolve’ into the liquid. When cooking brown rice, the rice does not dissolve, but rather absorbs the water and goes soft. This is because the oats are high in soluble fibre, whilst brown rice is high in insoluble fibre.

Benefits

As fibre can help you feel full for longer, it can be a useful tool when trying to manage your weight. It can also help control your blood glucose and cholesterol levels. Having a diet high in fibre can also reduce your risk of cardiovascular disease, type 2 diabetes and bowel cancer.

How much?

According to EFSA (European Food Safety Authority) adults should be aiming for around 25g of fibre per day. Most people aren’t eating enough. On average, people manage to eat around 14g of fibre per day.

Increase your fibre intake

If you want to increase your intake of fibre, it is important that you do so gradually. Increasing your intake too rapidly can result in stomach cramps and leave you feeling bloated. You should also make sure you drink plenty of water, aim for 6-8 glasses per day.

You can increase the amount of fibre in your diet by ensuring your diet contains plenty of fruit and vegetables, opting for wholegrains (brown rice/bread/pasta over white), leaving the skin on potatoes and adding beans or lentils to your soups and salads. Ensuring a vegetarian meal once per week is a great way of upping your fibre intake #meatfreemonday!

What does 25g a day look like?

fibre in a dayIBS

People who have digestive problems or IBS (irritable bowel syndrome) may need to adjust the type and amount of fibre they have in their diets depending on their symptoms. This is something that needs to be assessed on an individual basis. You should see your doctor or dietitian for more advice regarding this.

More information

Fibre-rich foods
General information on fibre from patient.co.uk
NHS information on constipation
NHS information on diarrhoea
NHS information on IBS

Healthy Living, Nutrition

How to gain weight

I saw a post on Facebook yesterday which reminded me of my initial idea I had months ago for this post. Dietitians don’t just work with people who want to lose weight or in health promotion. Actually, before I came to Belgium, a lot of my work was helping people gain weight. Especially for dietitians who work within hospital settings, a lot of the time we help build up those who are struggling, for whatever reason, to maintain weight.

Of course this doesn’t just go for ill people in hospital, some people find it difficult to maintain weight generally. For some, maintaining or gaining weight is as difficult as it is for others to keep it off.

Energy-dense foods such as chocolate, cake and pastries may help us gain weight, but they’re not going to be providing us with many other nutritional benefits. So, how does one go about gaining weight in a healthy way?

Little and often
Small frequent meals (or SFM, for those of us dietitians who like our acronyms!). This technique is particularly helpful if you don’t have a very big appetite, or aren’t able to manage a large meal. Some people naturally prefer to graze all day rather than concentrate calories into three meals, and that’s fine, whatever suits you and your stomach!
If you are already managing three meals per day, you should try and incorporate snacks between each meal to up your calorie intake (see below for some healthy snack ideas).

Snacking
Nuts, seeds and dried fruits are all healthy snacks that are easy to pick at and convenient to have at your desk. A handful of nuts will provide you with micronutrients, good fats, protein and those much needed calories, so get snacking! You can also add seeds or nuts to your meals, they taste great on porridge and in salads. Try having peanut butter on toast as a snack or, if you haven’t already seen, check out my healthy flapjack recipes.
Of course fruit is a healthy component of any diet, but dried fruit especially is useful when trying to increase your calorie intake. Not just because it’s easy to store in your desk drawer, but compare eating 5 plums to 5 prunes…I know which I’d find more manageable!

Think full fat dairy
Sweets, cakes and goodies aren’t the only foods that are fairly energy dense. Dairy products are convenient snacks and a good source of protein and calcium. A 30g portion of cheese contains around 100 calories. Sprinkle on top of your meal, snack on some cheese and crackers, add it to your salads…the choices are endless!
If you currently use skimmed or semi-skimmed milk switching to full cream could make a difference to your total calories. Half a pint of full cream milk contains around 100 calories more than skimmed. Incorporate into your diet through making fruit and vegetable smoothies or hot, milky drinks. You can also try adding full cream milk to soups, curries or other sauces (a little cream and coconut milk may also work well here, depending on the dish!)

Good fats
You may know that there are ‘good’ fats and ‘bad’ fats, but do you know that calorie wise, all fats are the same? Fats are the most calorie-dense nutrient, containing 9 kcals per gram. Naturally, it would seem more healthful that rather than upping your calorie intake using bad fats, you increase your intake of good fats, right? Well I’ve already mentioned some sources of good fats (nuts above) but the fats found in avocado, oily fish and olive or rapeseed oils will provide you with the calories and a dose of other good things too. Try making a guacamole dip or adding avocado to your lunch, aim to have oily fish 1-2 times per week and add an olive oil dressing to your vegetables.

Cooking methods
When I’m talking health promotion, there are certain cooking methods that I recommend to reduce fat and calorie intake. For people who are struggling to maintain or gain weight, certain cooking methods will increase the calories found in that meal. Using ‘good’ fat oils, such as olive or rapeseed, and adding them in when cooking will increase the amount of calories in that meal. For example, consider frying fish or roasting vegetables, rather than baking or boiling them.

Adding in
Think about your current routine, and reflect on where it may be possible for you to add something extra in. Think about your meals, snacks and drinks. Even making those 3 coffees milky ones could make a difference. You may be able to try something relatively simple such as increasing the portion sizes of the food you eat, topping it in cheese or serving it with a side of avocado, having a snack of cheese and biscuits or even introducing something for dessert.

 

Not all of these tips will be suitable for everyone, and if you’re really struggling to maintain your weight I’d recommend that you seek out personalised help from a dietitian.

Nutrition

Nutrient Nugget – Vitamin C

Why do we need vitamin C?

Vitamin C, also called ascorbic acid, has a huuuuuge list of functions. It’s an anti-oxidant, which means it helps to keep your cells healthy and reduce risk of cardiovascular disease, diabetes and inflammatory diseases. Vitamin C is also required to make collagen; a type of protein found in connective tissue (skin and blood vessels), which makes vitamin C is essential for muscle maintenance. It activates many hormones and enzymes, including those linked with bile production and liver metabolism. Plus, vitamin C plays an important role within our nervous system, aids wound healing and helps our body absorb iron. See, I said it was a long list!

citrusWhere do we get it from?

Our bodies are unable to make vitamin C, so all of what we need has to come from our diet. Vitamin C is found in lots of fruit and vegetables; oranges and other citrus fruits, kiwi, mango, blackcurrants, tomatoes, peppers, broccoli, potatoes, sweet potato and brussels sprouts.

 

How much do we need?

Adults are recommended 40 milligram (mg) per day* (Department of Health, 1991). Pregnant women should intake an extra 10mg for the last trimester, and breastfeeding women are advised to aim for a total of 70mg per day. Recommended intakes for other ages are outlined below:
0-1 year: 25mg
1-10 years: 30mg
11-14 years: 35mg

*People who smoke regularly use up more vitamin C and so may require up to 80mg per day.

To put this into perspective, a small orange contains 50mg of vitamin C, a medium sweet potato has about 20mg and a cup of broccoli will provide you around 80mg. As you can see, if you eat fruit and vegetables, you should have no problem reaching your recommended intake!

What if we don’t get enough?

You may have heard stories of when sailors and pirates used to suffer from a disease called scurvy. This is the name given to the disease caused when we don’t have enough vitamin C. Luckily, it’s not very common anymore apart from those who do not consume enough fruits and vegetables. Symptoms include; feeling fatigued, muscle weakness, irritability, pain in joints, bleeding gums and red/blue spots appearing on your skin. The disease is treated by the person taking vitamin C supplements and eating foods high in vitamin C.

What if we get too much?

Having over 1000mg (20 oranges!) can cause abdominal discomfort, stomach pain, flatulence and diarrhoea. Some people take high doses of vitamin C because they believe that it can help prevent the common cold. There is little evidence to support complete prevention, but high doses may help reduce the severity of some symptoms. In addition, it is likely that anything over 500mg of vitamin C at any one time won’t be absorbed.

Where can I find out more?

NHS Choices – Vitamin C
NHS Choices – Scurvy
Vitamin C and the common cold

Department of Health (1991). Dietary reference values for food energy and nutrients for the United Kingdom.

Nutrition

Nutrient Nugget – Iron

Why do we need iron?

Iron plays an important role in several essential bodily functions. It’s a crucial ingredient for haemoglobin, the substance found in red blood cells that carries oxygen around the body. Without oxygen, our organs and cells would not be able to respire; a process that keeps us alive! Although transport of oxygen is a principle function of iron, it is also a component of enzymes and helps with energy production.

IronWhere do we get it from?

There are two types of iron; haem and non-haem. Haem sources of iron are found in meat and fish, and are more easily absorbed by the body than non-haem sources. For this reason, vegans and vegetarians should take extra care to include plenty of iron rich foods in their diet. See my post on ‘how to be a healthy veggie‘ for more information.

Foods containing high levels of iron include; meat (especially offal), fish, eggs, dark green vegetables (spinach, swiss chard, kale, bok choy), lentils, beans (kidney, black, chic peas), wholegrains, nuts and dried fruit.

Some foods, such as soy bean products (milk, yoghurts and tofu), breakfast cereals and flour are fortified with iron. These can be a handy source, especially for fussy eaters, so check the labels of your favourites!

A handy hint: Vitamin C can help our body absorb more iron. So by having a source of vitamin C alongside your meal, you’ll get the most iron you can from it. Good sources of vitamin C include; citrus fruits, peppers, broccoli and sweet potato.

You should also avoid having tea and coffee at the same time as meals, as they contain phytates which bind with the iron and make it more difficult for the body to absorb.

How much do we need?

Iron reference nutrient intake gradually increases throughout childhood. The recommended daily intake for the adult population is 8.7mg for men and 14.8mg for women. Women have a higher requirement to allow for losses during menstruation (Department of Health, 1991).

Below shows the amount of iron contained in 50g of;

Liver* = 5mg

Lentils = 1.5mg

Dried apricots = 2mg

Broccoli = 0.5mg

Breakfast cereals (30g portion) = 4mg (depends on cereal)

An average steak will provide about 7mg of iron

*Liver is not recommended during pregnancy due to its high vitamin A content.

What if we don’t get enough?

Iron deficiency anemia or IDA is one of the most common nutritional deficiencies in the world. It occurs when a lack of iron in the body results in a low number of red blood cells. IDA can result in the following symptoms; fatigue, breathlessness, insomnia, loss of appetite, decreased immunity, heart palpitations and a tingling sensation in your fingers and toes (paraesthesia).

IDA is usually easily treated by taking a iron supplement which boosts the levels of iron in your body. Recurrence can then be prevented by ensuring a diet rich in good sources of iron. Some women who regularly have heavy periods may need to take an iron supplement, ask your doctor for more advice.

What if we get too much?

Too much iron usually occurs through use of a supplement but can lead to constipation, nausea, vomiting, and stomach pain. Intakes of less than 20mg are unlikely to cause any problems, but very high doses can be fatal, so be sure to keep iron supplements out of reach of children.

Where can I find out more?

NHS Choices – Iron deficiency anaemia

NHS Choices – Iron

Department of Health (1991). Dietary reference values for food energy and nutrients for the United Kingdom.

Nutrition

Nutrient Nugget – Calcium

Why do we need calcium?
Calcium is the most abundant mineral in the body. Most people know that calcium is important for bone and teeth health, but it also helps with nerve signalling, blood clotting and regulating muscle contractions (including the heart).

Where do we get it from?
Good sources of calcium include dairy products, soy beans, green leafy vegetables (broccoli, kale and cabbage) and nuts. Any fish where you eat the bones (eg. sardines or white bait) will also contribute calcium to the diet.
Fortified flour is often used to make bread and other products, so although this is not a rich source, some of our calcium comes from these products as they are consumed so regularly. Some brands of tofu and breakfast cereal are fortified with calcium too (check the label).

How much do we need?
Calcium requirements change for different ages. This is because of needs associated with bone growth. Below shows calcium reference nutrient intakes for different ages (Department of Health, 1991).
0-12 months: 525mg
1-3 years: 350mg
4-6 years: 450mg
7-10 years: 550mg
11-18 years: 1000mg (male) and 800mg (female)
19+ years: 700mg

A 200ml glass of cows milk will provide you with 250mg of calcium and a pot of yoghurt contains about 150mg. Vegan sources are not as rich, with 100g of broccoli providing around 40mg of calcium.

What if we don’t get enough?
Not having enough calcium over a long period of time could lead to osteoporosis and increased risk of bone fractures in later life. It can also cause development of rickets in children. See my post on vitamin D for more information on rickets.

What if we get too much?
Too much calcium usually occurs through use of a supplement but can lead to stomach pain and bowel disturbances. Intakes of less than 1500mg are unlikely to cause any problems.

Where can I find out more?
NHS Choices
The Vegetarian Resource Group

 

Department of Health (1991). Dietary reference values for food energy and nutrients for the United Kingdom.

Nutrition

Quinoa

quinoaI’m pretty late to jump on the quinoa bandwagon, but now I keep finding new uses for it. So watch out for recipes using this baby!

As quinoa is something that’s increased in popularity only recently, I didn’t know that much about it nutritionally either. So I thought I’d share my research with you.

What is quinoa?
Hailing from South America, and a staple of the Inca people for hundreds of years, quinoa is a wheat free alternative to starchy grains. It has a lot of the properties of typical grains (like rice and pasta) but isn’t from the same family, it’s actually the same family as chard, beets and spinach. However, as it is a cereal product, it’s considered a carbohydrate on the Eatwell Plate.

What about nutritionally?
Like other grains, quinoa is packed with fibre which helps keep your bowels healthy. It’s also a handy source of protein, especially for vegetarians or vegans; providing 9 essential amino acids in higher concentrations than found in other grains.
Having fibre and protein together helps keep you full, so the mixture of these two found in quinoa also means that it is fabulous for those trying to lose weight. Quinoa is also gluten free, making it an excellent addition to the pantry of any coeliac.
Finally, quinoa contains lots of micronutrients including; magnesium, iron, B-vitamins and calcium.

Per 100g serving
(approx. 50g raw)
CALORIES 120kcal
PROTEIN 4g
CARBOHYDRATE 21g
FIBRE 3g
TOTAL FAT 2g
SATURATED FAT 0.3g

What can it be used for?
Quinoa is incredibly versatile. On its own it has a subtle nutty taste which makes it a useful addition for soups, stews and curries as it won’t change the flavour too much. I would say it has a similar light texture to couscous, but has a slight crunch. I’ve eaten it hot and cold and both ways it tastes fantastic! I’ve used it as a replacement to rice, oats and even trialled some recipes that traditionally use pasta. I’ve also made quinoa porridge, see my recipe here.

How do I cook it?
It’s really important to rinse your quinoa before cooking it, as otherwise the coating on the grain leaves a bitter taste. Once you’ve rinsed it well, you can cook it as you would rice. It takes about 15 minutes on the hob and you can tell when it’s done by watching out for the seeds splitting open slightly.

Conclusion
Quinoa features regularly in our diet, and I’m enjoying experimenting with what else I can do with it. It’s a great alternative to traditional grains and has added nutritional benefits too. Variety is the spice of life so as far as I’m concerned it’s a fab addition to a healthy balanced diet.

There are quite a few quinoa recipes online, but keep an eye out for the ones I post too. I’d also love to hear your suggestions!

Nutrition

Nutrient Nugget – Vitamin D

This week I’m going to start a new series of posts called ‘nutrient nuggets’. I thought it would be helpful to give you snippets of information about a particular nutrient, mineral or vitamin.

So, as it’s summer…where better to kick off than with vitamin D?

Why do we need vitamin D?
Vitamin D helps regulate the amount of calcium and phosphate in the body, these are all are used in combination to help make our bones strong and healthy. Vitamin D has many other important roles in the body, including helping maintain muscular strength, immune function and reducing inflammation. Vitamin D also plays an essential role in cell growth; where cells become specialised for a specific function.

oily fishWhere do we get it from?
The majority (80-90%) of vitamin D is obtained from the sun; when sunlight hits the skin, it causes a reaction under our skin which produces vitamin D.
There are only a couple of dietary sources of vitamin D. Good sources are; oily fish (herring, mackerel, salmon, sardines etc), eggs and fortified fat spreads (required by UK law to contain vitamin D). Some yoghurts and breakfast cereals are also fortified with vitamin D.

How much do we need?
Exposing your face and forearms to the sun a few times a week should be sufficient to maintain good vitamin D levels through the summer. (Remember to cover up and use suncream when out for extended periods and at the hottest times of the day to reduce the risk of skin damage and skin cancer). However, through the winter, it is not possible for our bodies to use sunlight to make vitamin D and this can lead to low levels. It is recommended that everyone in the UK consider taking a 10 microgram (μg) vitamin D supplement from October to March.

Certain population groups such as pregnant women, babies, people who cover their skin when outdoors and those with darker skin are at increased risk of vitamin D deficiency. For these groups, a daily 10 microgram (μg) vitamin D supplement is recommended throughout the year.

The Department of Health in the UK recommends that pregnant and breastfeeding mums should also take a 10μg supplement of vitamin D to ensure she is meeting her nutritional requirements and to help build adequate nutrient stores. Breastfed babies and children aged 1 to 4 years should also take a daily vitamin D supplement (up to 10 micrograms (μg)). Formula fed babies should not take vitamin D unless they are having less than 500ml formula a day as formula is fortified with vitamin D.

What if we don’t get enough?
Early signs of deficiency can be fatigue, muscle aches/weakness and bone pain. A lack of vitamin D over the longer term can cause a bone deformity disorder in children called rickets. Rickets causes the bones to become soft, tender and weak. It can also cause problems with developing teeth. In adults, a similar bone softening condition called osteomalacia can occur.

If you are concerned about your vitamin D levels, you should speak to your doctor, or ask to be referred to a dietitian.

What if we get too much?
Too much vitamin D can upset the balance of calcium and phosphate, provoking the removal of calcium from bones, weakening them. This imbalance can also lead to excess calcium being absorbed rather than being excreted. Excess calcium can be deposited in the kidneys and cause damage.

Given the low amount of vitamin D in most diets, it is most likely vitamin D in excess would occur as a result of taking too higher dose of supplement. The NHS state adults should not take any more than 100 micrograms (μg) of vitamin D per day, children age 1 to 10 years no more than 50 micrograms (μg) and babies less than 1 year no more than 25 micrograms (μg) daily.

What can we do to prevent deficiency diseases?
Rickets and osteomalacia can be prevented by eating a healthy, balanced diet incorporating some sources of vitamin D and taking supplements as recommended above. The NHS also advises 20-30 minutes of sun on the face and forearms a couple of times a week. Please note: You should still use suncream to protect your skin.

Where can I find out more?
Patient.co.uk
NHS: Vitamin D
Find out more about rickets on the NHS Choices website, here.
The Journal of Family Healthcare have a great article detailing causes, prevalence and prevention of rickets.

 

[Updated May 2020]

Nutrition, Weight Loss

Fats: which ones should we choose? (Part 2)

This is a continuation of my post regarding fats, see part 1 here.

What are omega-3 and omega-6?

Omega-3 and omega-6 are essential fatty acids found in polyunsaturated fats. They are essential because they cannot be made by the body and are required for good health, so it’s important that we get these fatty acids from our diet.

Omega-3, or alpha-linolenic acid, can be found in rapeseed oil, dark green leafy vegetables, walnuts and seeds. Some eggs are also fortified with omega-3. Oily fish (salmon, mackerel, sardines and herring) are a rich source of a specific type of omega-3 that can help reduce inflammatory responses and blood clotting, thereby reducing risk of heart disease. Current recommendations state 1-2 portions of oily fish per week. Omega-6, or linoleic acid, is found in vegetable and nut oils such as sunflower and peanut oil.

There is growing evidence to suggest that omega-3 and omega-6 can help lower our risk of heart disease and some studies show reduced risk of type-2 diabetes and Alzheimer’s disease.

Coconut oil; good or bad?

There have been a lot of health claims about coconut oil recently, but is it all it’s cracked up to be?

Firstly, it should be noted that coconut oil is around 92% saturated fat. As you can see in the graph below, this is extraordinarily high and, using the general ‘rules’ regarding saturated fats coconut oil should be avoided. However, the composition of coconut oil is unusual. A large proportion of the fats found in coconut oil are medium chain fatty acids.

Oil fat content

…What are medium chain fatty acids?

Fatty acids are the bits attached to the glycerol backbone (go back to the structure of a triglyceride explained in part 1). Short, medium and long are terms used to indicate the length, or number, of carbons present in the fatty acid chain. Short (0-6 carbons) and medium chain (6-13 carbons) fatty acids are digested, transported and metabolised more quickly than long chain fatty acids (14+ carbons). This could mean that the high concentration of medium chain fatty acids found in coconut oil results in it behaving differently within the body to most saturated fats.

It may also be that the length of the carbon chain changes the impact the fat has on blood cholesterol levels. For example, research suggests that long chain fatty acids increase total and LDL (‘bad’) cholesterol while medium chain fatty acids increase the HDL (‘good’) cholesterol and have a neutral effect on LDL. However, more research is needed to confirm this.

What about the other health claims of coconut oil?

About 49% of the medium chain fatty acids found in coconut oil is lauric acid. It has been suggested that lauric acid has special antibacterial properties. However, many of the health claims that exist around coconut oil and it’s antimicrobial properties are not yet proven. There are also claims suggesting coconut oil increases metabolism therefore aiding weight loss. Unfortunately, very few studies investigate health benefits of coconut oil, especially when compared to the substantial evidence backing health benefits of mono and polyunsaturates (see part 1). Plus, it is consumed in such low quantities that any impact on microbes or metabolism is likely to be minimal.

Having said this, coconut oil is fine to use in small amounts or as a replacement to other oils in cooking. It can add a tasty nutty flavour to food and the presence of medium chain fatty acids may have a beneficial effect on blood cholesterol. Coconut oil, in particular, is a fat that requires lots more research!

So what fat should I choose?

There are lots of different types of oils and spreads available, and people may use different types for different things.

The biggest difference between butter and different types of spread is the saturated fat content. The graph below demonstrates the amounts of fat present in different types of spreads. (Values have been averaged from commonly used brands but can vary).

Fat spreads comparison image

Which oil and spread you choose is likely to depend on lots of things; taste preference, health benefits, cost, habit etc.

In summary, to choose a fat low in saturates with higher proportions of mono and polyunsaturates is best for heart health, i.e rapeseed/olive oils and spreads. However, if used sparingly (as any fat should be anyway!), fats with higher amounts of saturates (such as butter and coconut oil) can be incorporated as part of a balanced, healthy diet.

It’s important to remember that all oils and spreads are fats, so whatever ones you use should be in small amounts, especially if you’re trying to lose weight.

Nutrition, Weight Loss

Fats: what, why and how much? (Part 1)

At times, it seems like the media change their mind on a daily basis about whether fat is good or bad, which ones are better and which ones to avoid. So, to clear it up, I’m going to start at the beginning…

What is a fat?

In chemistry, fats are called lipids. There are three main types of lipids; triglycerides, phospholipids and sterols. Most of the fat we eat is in the form of triglycerides, so for this blog post I’ll be looking specifically at these.

Triglycerides are made up of 4 components; a glycerol backbone and 3 fatty acid chains. They look a bit like this;

Paint fat

Fat structure

OR

 

 

 

 

 

The fatty acid chains can be saturated or unsaturated, this describes how the molecules in the fatty acid are joined together. Saturated fats have no double bonds, unsaturated fats have at least one double bond (as seen in the bottom fatty acid chain above). Generally speaking, saturated fats tend to be solid at room temperature and are from animal sources. Unsaturated fats are liquid at room temperature and tend to come from vegetable or plant sources.

Why do we need fats?

Fat provides energy; around 9 kilocalories (kcals) per gram. It’s important that we have some fat in our diet because it’s needed to transport and aid absorption of fat soluble vitamins. Fat also provides vitamins A, D and essential fatty acids that cannot be made by the body. However, too much fat can lead to weight gain and put us at risk of health problems in later life.

What are the different types of fat?

There are three main types of fats; saturated, monounsaturated and polyunsaturated. Most foods contain a mixture of all of these, but usually one type of fat is present in larger quantities than the others. There are also trans-fats, these are a specific type of unsaturated fatty acid. Trans-fats are found in low levels in some foods but are also formed in food manufacturing.

Saturated and trans-fats are less healthy, because they bring about an increase in overall blood cholesterol levels. Foods high in saturates include; fatty cuts of meat, butter, cream, cheese and pastries. Trans-fats are formed when oil undergoes a process called hydrogenation, the hydrogenated fat can then be used for frying or as an ingredient in processed foods.

We should all try to have less saturated and trans-fats in our diet. Saturated fat can be reduced by choosing leaner cuts of meat or trimming off the fat, using low fat dairy products and grilling or poaching foods rather than frying or roasting them. As the negative effects of trans-fats have become more evident, their use in food manufacturing has declined. As a result, most people eat under half the recommended maximum of trans-fats, so saturated fat presents a much bigger problem. However, it is still worth checking labels and choosing oils that do not contain hydrogenated or partially hydrogenated vegetable oil.

Mono and polyunsaturated fats are better for us as they can help lower blood cholesterol. Sources of monounsatured fats include olive oil, nuts and avocados. Polyunsaturated fats can be found in rapeseed oil, sunflower oil, oily fish and nuts.

However, a fat is still a fat and to prevent gaining too much weight and increased risk of diseases in later life we shouldn’t eat too much of any type of fat – even the ‘good’ ones!

So how much fat should we eat?

Current recommendations state that no more than one third of our daily energy should come from fats. This works out at between 50-100g of fat per day depending on your nutritional requirements. Of this, less than 10% of our daily total energy intake should come from saturated fats (around 20g for women and 30g for men) and no more than 5g per day of trans-fats. Fat and saturated fat content of most food items can be found on the food labels.

Generally speaking, choosing plant sources of fat that contain mono or polyunsaturates where possible is best for heart health. But we should try to prevent over-consumption of any type of fat in order to prevent weight gain.

 

…Part 2 of ‘FATS’  explores fat makeup of different oils and spreads; which ones we should choose? I’ll also be looking at omega-3, omega-6 and the facts behind coconut oil.