So we established in Part 1 of this blog that the guidelines suggest that two or more serves is how much fruit we should consume. However, for some of us, it’s really easy to over consume. And this may well be having a negative impact on our health. Now I finished the previous blog with suggesting that somewhere between 2 to 3 serves is most ideal. But what if I have metabolic issues? Are there better and worse fruits to consume?
How much fruit should I consume to protect the heart?
Interestingly, many studies have looked into this question. However, they tend to combine fruit and vegetables together making it hard to conclude. One study by Lai et al (2015) looked into this and found that in a group of UK women the risk of death from a cardiovascular event decreased with more fruit even with over 4 serves per day. It’s would be easy from this to conclude that more is better right?
Another UK study looked at the risk of death from cardiovascular disease or cancer in both men and women (Oyebode et al 2013). What they found was that increased vegetable consumption was more protective than fruit. When they looked at just fruit intake the greatest benefit was at 3 serves per day. Depending on the model used, an increase in serves beyond this either had no further benefit or increased your risk.
How much fruit should I eat for metabolic health?
So we know that 3-4 serves of fruit is good for the heart. But what about people who are at risk of or want to prevent diabetes?
We have a good amount of evidence here that perhaps we shouldn’t be eating too much fruit. In fact a very large meta-analysis of 7 studies by Li et al (2015) concluded that those who had a fruit intake of around 200 grams per day (about 1.5 serves) were less at risk of developing diabetes. While it certainly is not good to have no fruit in a day, having 3-4 serves increased your risk comparatively. And from there, things tended to get worse with increased fruit consumption.
Furthermore, a study by Zhang & Jiang (2015) tended to corroborate this finding with two serves a day being the “sweet spot” for reducing the risk of developing diabetes in a study of over 200,000 individuals. And similar to the Li et al (2015) meta-analysis, they found a similar U shaped curve when consumption increased above 2 serves with 4 serves being as high a risk as having no fruit at all.
So there may be such thing as too much of a good thing. And like most things we need to consume fruit in moderation, especially if we’re at risk of diabetes and metabolic conditions.
But are some fruits better than others? Well the short answer to this question is “yes”
Fruits that when you consume more to have a health benefit
Interestingly, most studies will show that vegetables have a stronger association in reducing premature death than fruit (Oyebode et al 2013). However, some fruits, when you consume more tend to reduce your risk of either cardiovascular disease or diabetes.
Lai et al (2015) found that a greater intake of citrus was associated with a lower risk of fatal stroke in women. While grapes were seen to be more protective against a fatal cardiovascular event. When we look at the risk of diabetes, Alperet et al (2017) found that temperate fruit such as apples was associated with a loser risk of diabetes in women. Both citrus and grapes tended to lower the risk of diabetes for both men and women.
So it appears there are some common threads: citrus and grapes tend to reduce our risk. But what about fruits that perhaps aren’t so good for us to overconsume?
Fruits that may not be good for us when we over consume
Firstly, a common theme in most studies is that fruit juice is not fruit! Imamura et al (2015) found that while not quite as bad as soft drink (every serve a day increased your risk of diabetes by 18%), every serve of fruit juice increased your risk by 5%.
When it comes to increasing your risk of cardiovascular disease it seems that any canned fruit will do this (Oyebode et al, 2013). They found that every daily serve increased your risk by 17%.
Now there it appears that too much tropical fruits (bananas, mangoes, melons) will increase your risk of diabetes and these should be limited to less than one serve a day (Alperet et al 2017). Interesting Huang et al (2017) found that tropical fruit increased the risk of gestational diabetes.
Finally, Alperet et al (2017) also found that higher glycaemic index (GI) fruits had a greater risk than lower GI fruits. While these fruits tend to be more tropical in nature here’s a list of fruits with a GI greater than 50:
- Watermelon – 72
- Pineapple – 66
- Rock melon – 65
- Paw Paw – 60
- Canned Peaches – 58
- Banana – 56 (although increases with ripeness)
- Kiwi Fruit – 52
The take home message about how much fruit you should eat
- The amount of fruit you eat is important. 2-3 serves per day is probably best for your long term health but more than 4 may increase your your risk of metabolic conditions such as diabetes.
- Try and limit your consumption of high glycaemic fruits like tropical fruits and treat them as “treats”.
- Don’t count fruit juice as a fruit, if anything it should be treated more like soft drink
- Aim to get the bulk of your 2-3 serves of fruit a day from lower or moderate GI fruits. Fruits like grapes, apples and citrus all appear to reduce your risk of health conditions as you age.
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Sleep Awareness Week is here and what better time to remind us all the importance of a good night’s sleep.
Do you consistently get less than six hours sleep?
Or, do you frequently wake during the night?
If you do, don’t fear, as we have a few practical sleep hygiene tips to help improve your sleep patterns. (more…)
Picture this… Its January 1st. This year you want to lose weight! In fact you have
already started to cut out the cake at lunch, park your car further away from work and have joined the local yoga class. You have been weighing yourself daily and watching the numbers on the scales decrease. You have started off strong…
But then the weekend hits, you have that important birthday and you become discouraged. This weight loss thing doesn’t seem so fun anymore and you may have just convinced yourself you just don’t have self discipline! You have already resigned to the fact that any further weight loss is in fact impossible and you might was well start eating the cake at lunch time again. You begin to put that weight back on and focus your energy on something else. This vicious cycle continues again and again. Does this sound familiar?
How do we break out of the vicious cycle?
Goal setting helps quantify and clarify the ‘how,’ the ‘what,’ the ‘why’ and the ‘when’ behind these statements. The aptly named S.M.A.R.T goals provide you with direction, structure, accountability and give you a deadline to meet. The SMART criteria is as follows:
- Identifies exactly what you want to achieve.
- Studies have shown that task specific and challenging goals lead to higher performance than ‘do your best’ or no goals at all.
- Feedback or reward has been shown to increase task performance
- Places a measurable value on the task for example; centimetres; dress; minutes;
- It allows for re-evaluation to objectively review a goal
- Do you really believe you can do this?
- Your goal must challenge you enough to be outside of your comfort zone, however should be within your reach.
- Are both the goal and the timeframe you set to complete the goal realistic?
- Going from sedentary to running marathon distances may be realistic but doing this in 2 weeks may not be.
- Set a time frame to achieve this goal by. When do you plan to achieve this goal?
- Not only does writing down your goals increase success rate, but it has also been shown to improve happiness, satisfaction levels and also creates a sense of achievement.
A goal without a date is just a vision
- Try and limit the amount of goals you have at one time and prioritise them
- Follow the SMART goals principle and write them down
- Re -evaluate: goals are there to be adaptable and flexible to your current situations and change, a review of your goals with change of circumstances or a period of time is essential to the goal setting process.
- Share them with the people who will help you achieve them; choose wisely!
If you currently do not have any clear goals written down, I encourage you to set some time aside or book in for a review with your trainer to nut out what you want to achieve. Goal setting is something which most of us recognise the importance of to achieve success, so lets be SMART about it!
Last week I saw a report on the ABC about the growing prevalence of overweight or obese kids in Australia, and it sparked a lot of angry thoughts! As one my areas of passion is seeing healthy active kids!
The stats, as you can imagine, are scary: Back in 2000, approximately 20% of teenagers were overweight or obese, now its 25% and a study conducted by the Victorian Dept of Hman Services predicts that this number will increase to 33% by 2025 (Future prevalence of overweight and obesity in Australian children and adolescents, 2005-2025 Department of Human Services, March 2008)
The consequences are sad and cruel: greater prevalence of cardiovascular disease, Type 2 Diabetes, a whole range of cancers, and mental health issues.
The reasons are both staggering, yet unsurprising:
The study reported on by the ABC was conducted by the Cancer Council and National Heart Foundation, and it revealed teens were spending too much time in front of the television with 58 per cent of students having at least three televisions in their home and 40 per cent with video games in their bedrooms. 75% of teenagers were spending more than two hours in front of screens (for school work or entertainment). A huge 82% are not engaging in more than 60 minutes of physical activity per day.
So what are we going to do about this sad state of affairs? All this takes me back to a paper I was privileged enough to co-author a few years ago. It showed that not only are both adults and children under active, but that the association between parents and their kids’ physical activity is decreasing. So the behaviour modelling strength of parents’ activity is influencing kids less! While the reason why is unclear; my guess is that its due to our changing behaviour patterns. We just don’t see as many families going for walks or bike rides together. You don’t see as many dads kicking the footy with their kids. Now we go to the gym or social sport on the way to or from work, and we are ‘done’ by the time we get home. So while we may be active, our kids don’t see us being active, so they don’t learn from our exercise behaviours!
So lets get out with our kids more. Even when I’m being active on my own, I try to make a point of telling my kids how much I enjoyed my run or bike ride around Adelaide’s beautiful trails!
Martin M, Dollman J, Norton K, Robertson, I. (2005) A decrease in the association between the physical activity patterns of Australian parents and their children; 1985-1997, Journal of Science and Medicine in Sport, 8(1): 71-76.
I have this conversation with clients at least once a week, so I thought I’d share it here for you as well. Now, while I’m an Exercise Physiologist (and not a dietician), the majority of our clients ask about dietary advice, as it’s part of the lifestyle behaviours that we often coach our clients through. We make sure that our advice stays within the scope of sharing general principles about food, supported by research from biochemistry and physiology.
So the question of ‘carbs’ intake comes up very often, as the message that a diet ‘lower in carbs’ leads to greater weight loss is well spread. This is the type of eating that I also stick to, for a number of reasons that I’ll get into later. But for now I want to address a significant part of this discussion that is often overlooked: The glycemic load (GL). Now, most people are aware of the glycemic index (GI), which relates to how quickly a food containing carbohydrate raises blood-glucose levels, depending on the type of carbohydrate chain involved. Typically, the quicker a food’s carbohydrate is broken down and absorbed into the bloodstream, the higher the GI.
The glycemic load estimates how much (rather than how fast) the food will raise a person’s blood glucose(sugar) levels after eating it. So it incorporates the GI, but very importantly, it also depends on the AMOUNT of carbohydrates the food contains!
So while a dark bread has a low glycemic index, due to the complexity of the carb chains, it has a high glycemic load, due to the many and long carbohydrate chains in it! So it provides a LOT of carbohydrate and calories. While the insulin spike won’t be high, it will be prolonged. its a slow cooker! In contrast, most vegetables will be both low GI and low GL, a perfect combination! in addition, they’ll be high in nutrient value (vitamins and minerals) as well as relatively lower in calories.
So don’t want to avoid carbs, but be aware of the total LOAD of the carbs you are eating, and make sure these match your personal energy requirements! LOAD up on the veges, and perhaps reduce the bread!