Amanda Johnson

Aspartame – is it safe? - Food Stuff

Jun 16, 2010

The safety questions around aspartame were back on the agenda yet again today, with a Coca Cola funded webinar presentation by Dr Bernadene Magnuson. Dr Magnuson, a Senior Scientific and Regulatory Consultant at Cantox Health Sciences International and University of Toronto Associate Adjunct Professor of Nutritional Sciences, gave an excellent review of the latest research on the safety of aspartame — very similar to the presentation she gave in Wellington 18 months ago, which I attended. I think most of us are fairly well aware by now that aspartame is safe, given the comprehensive reviews of this sweetener that have taken place by many of the food safety agencies around the world. Not to mention the fact that there is no plausible mechanism by which it could be deemed to be harmful. Aspartame is simply two amino acids … Read More

What’s worse — sugar or fat? - Food Stuff

May 19, 2010

This is a question addressed in the latest (June 2010) issue of the American Journal of Clinical Nutrition (AJCN). For many years now the key nutritional advice, particularly for those at high risk of cardiovascular disease, has been to reduce saturated fatty acids (SFA) and replace these with complex carbohydrates. As a result, reports Frank Hu in his recent AJCN editorial, a substantial decline in energy intake from total and saturated fatty acids has occurred in the United States. At the same time, this has spurred an increase in consumption of refined carbohydrates and added sugars. Is this dietary shift contributing to the twin epidemics of diabetes and obesity? The answer to this question may be ‘yes’! In a paper published in the June 2010 issue of the AJCN, by Jakobsen et al, the authors used substitution models … Read More

Should school kids be peddling junk food? - Food Stuff

Feb 23, 2010

It’s the start of the school year and our little boy, who has just turned five, started primary school a couple of weeks ago. Already he has come home with a big bag of 40 ‘Cookie Time’ biscuits that we are expected to sell for $1 a piece. As a dietitian, it doesn’t feel right to be promoting such an item — which from a nutritional point of view provides little more than energy, fat, saturated fat and sugar. And, when you think about it, there are around 320 kids at my son’s primary school; that means 320 kids each taking home and selling 40 cookies. By the end of this exercise, the school could have sold as many as 12,800 biscuits, providing over seven million kilojoules of energy and around a hundred thousand grams of sugar to … Read More

Fitness versus fatness - Food Stuff

Feb 16, 2010

It’s a long-standing debate — can you be fat and healthy as long as you are fit, or is it bad to be fat, full stop? The debate came to New Zealand earlier this month when Professor Steven Blair presented at a conference at the University of Otago on the crucial role of physical activity in the prevention and management of overweight and obesity. Commenting in the Otago Daily Times, Prof Blair states, ’I’ve been studying the cause of death in a select group of people for over 30 years and I’ve found that a sedentary lifestyle accounted for more deaths than anything else.” Prof Blair said he, himself, was overweight, but maintained he was healthy because he was fit. Prof Blair argues in his research that that regular physical activity clearly attenuates … Read More

Will drinking coffee help prevent diabetes? - Food Stuff

Dec 17, 2009

New research published in the December issue of Archives of Internal Medicine has found that consuming coffee reduces the risk of diabetes. The findings from this meta-analysis, based on over 500,000 individuals with over 21,000 cases of new-onset diabetes, confirm an inverse relationship between coffee consumption and subsequent risk of type 2 diabetes. There was also an inverse relationship between consumption of decaffeinated coffee and tea, and risk of diabetes. Individuals who drank three to four cups of coffee per day had an approximately 25 percent lower risk than those who drank between zero and two cups per day. In addition, in the studies that assessed decaffeinated coffee consumption, those who drank more than three to four cups per day had about a one-third lower risk of diabetes than those who drank none. Those who drank more than three to … Read More

Does fish oil help children to learn? - Food Stuff

Nov 11, 2009

A study featured on TV One’s Close-Up last night certainly hopes to show it does. This new New Zealand study is funded by natural health manufacturers Good Health, and if the fish oil supplements are proven to boost IQ, the results will be a big boost for the manufacturers. The research is being lead by Kerry Lee from Auckland University, and is looking at 200 or so normal children at West Harbour Primary School. Half have been receiving omega-3 capsules four times daily for 15 weeks and half have received a placebo. Results are due out in January 2010 and it will be very interesting to see if the omega-3 supplements do show any effect on learning in this group of normal children. This isn’t the first time omega-3 have been linked to learning and behaviour in children. Read More

Are vitamins killing you? - Food Stuff

Oct 29, 2009

‘Are vitamins killing you?’ — the latest instalment in TV3’s documentary series Inside New Zealand, broadcast October 28 — certainly grabbed our attention at the Science Media Centre this week. Although the title was a little dramatic, the programme did convey an important message: that excess intakes of vitamins can be harmful. The programme makers followed eight supplement-users over a period of six weeks. At the start of the programme seven of the subjects ceased to take their supplements, and one changed from taking bee pollen to taking a multi-vitamin supplement (the control). It was no surprise that initial blood tests demonstrated high levels of some vitamins in some subjects. After the six-week trial period, those who had ceased to take the supplements found the vitamin levels in their blood generally returning to normal levels. With the exception … Read More

Food label confusion - Food Stuff

Oct 23, 2009

It was interesting to see the whole issue of food labelling covered on Campbell Live last night. Food Safety Minister Kate Wilkinson, when approached by Campbell Live, was unable to even read the food label presented to her (she had the wrong glasses on) and commented that a lot of people ‘don’t necessarily have such an interest in the label’. I would disagree. Focus group research with consumers has demonstrated consumer demand for front-of-pack labels. This issue is not new. UK consumer research by the Institute of Grocery Distribution (IGD) in the late 1990s investigated nutrition labelling and found that levels of understanding were low, with labels described as ‘complicated, frustrating and illegible’. Terms such as ‘carbohydrate’, ‘saturates’ and ‘sodium’ were poorly understood and ‘kilojoules’ were perceived as irrelevant to adults. As a result of this … Read More

Europeans reject two thirds of proposed health claims - Food Stuff

Oct 08, 2009

The European Food Safety Authority (EFSA) last week published a series of opinions on ‘general function’ health claims compiled by Member States and the European Commission. Experts from the EFSA evaluated the scientific evidence for more than 500 claims. In a press release issued last week, the EFSA state: ’The opinions provide scientific advice on 523 health claims relating to over 200 foods and food components such as vitamins and minerals, fibre, fats, carbohydrates, ‘probiotic’ bacteria, and botanical substances. For approximately one third of the claims the outcomes of the evaluations were favourable as there was sufficient scientific evidence to support the claims. These related mainly to functions of vitamins and minerals, and also included dietary fibres, and fatty acids for maintenance of cholesterol levels, and sugar-free chewing gum for maintenance of dental health. Almost half of the … Read More

Does eating sweets make us violent? - Food Stuff

Oct 02, 2009

The most bizarre story in the media this week has to be the one suggesting that eating sweets in childhood causes violence in adults. The story was based on a study just published in The British Journal of Psychiatry. The authors tested the hypothesis that excessive consumption of confectionery at age 10 years predicts convictions for violence in adulthood (age 34 years). Data from age 5, 10 and 34 years were used. Results showed that children who ate confectionery daily at age 10 years were significantly more likely to have been convicted for violence at age 34 years, a relationship that the authors say was robust when controlling for ecological and individual factors. We all know that sweets aren’t very good for us. The evidence supporting the high consumption of sugars and sweets as a causative … Read More