Issue 2 | Volume 1 | July 2019 In this issue: Articles Do Low Carbohydrate Diets Negatively Affect Female Hormone Balance? Many people think that low-carb diets are negative for female hormone balance, menstrual cycles, and ovulation. But does this stand up to scientific scrutiny? Can You Be ‘Healthy at Every Size’? ‘Health At Every Size’ (HAES) has become a very popular ‘anti-diet’ movement, and while it’s goals a laudable and it results in benefits, can you actually be healthy at every or any size? Research reviews and commentary How reliable is the statistical evidence for limiting saturated fat intake? Most reviews and meta-analyses show no effect of saturated fat on mortality but the influential Hooper meta-analysis of 2015 suggested increased risk of death from saturated fat in the diet. But was this finding reliable? In a new study, Simon Thornley and colleagues cast doubt on the findings of the Hooper analysis. Association of changes in red meat consumption with total and cause specific mortality among US women and men: two prospective cohort studies A recent study has been highly promoted in the media as another ‘nail in the coffin’ for red meat, suggesting increased risk of death from eating red meat. But was this effect really shown? From the media Rebuttal to the Physician’s Committee for Responsible Medicine article: “Keto Diet Is Dangerous for Veterans with Diabetes” A recent article by vegan advocacy group PCRM has attacked using low-carb for veterans with diabetes. In this article, researcher Cliff Harvey…
Key Findings HAES results in significant and lasting benefits to self-esteem, body image, hunger cues, and cognitive restraint.These results are similar to social support programsHAES does not result in substantive benefits to physical health.A combined approach, focussed on psycho-social and physical indicators of health is likely to the best approach Traditional weight loss methods are based primarily on a medical model which treats obesity as a disease requiring diet, exercise, or pharmaceutical intervention. Conversely, the increasingly popular ‘Health At Every Size’ (HAES) movement believes that “individuals who are overweight and obese want to exercise and eat healthy foods, and they are capable of doing so when barriers are removed”.1 The Health At Every Size® Principles are: Weight Inclusivity: Accept and respect the inherent diversity of body shapes and sizes and reject the idealizing or pathologising of specific weights.Health Enhancement: Support health policies that improve and equalize access to information and services, and personal practices that improve human well-being, including attention to individual physical, economic, social, spiritual, emotional, and other needs.Respectful Care: Acknowledge our biases, and work to end weight discrimination, weight stigma, and weight bias. Provide information and services from an understanding that socio-economic status, race, gender, sexual orientation, age, and other identities impact weight stigma, and support environments that address these inequities.Eating for Well-being: Promote flexible, individualized eating based on hunger, satiety, nutritional needs, and pleasure, rather than any externally regulated eating plan focused on weight control.Life-Enhancing Movement: Support physical activities that allow people of all sizes, abilities, and interests to…
Most meta-analyses do not support the idea that saturated fat is a cause of heart disease but the 2015 meta-analysis by Hooper and colleagues suggested that saturated fat increased mortality. But was this study reliable? In a new analysis, Thornley et al., cast doubt on the reliability of this finding.
Key Findings Carbohydrate restriction does not result in alterations of ovulation, menses, or other indicators of women’s hormonal health. Low-carbohydrate diets have demonstrated positive benefits to women’s hormonal health. Extreme calorie restriction is likely to affect women’s hormonal balance and health. Those women who are leaner and exercise more are at greater risk of negative effects from excessive or prolonged energy restriction. A common claim currently doing the rounds, is that a low-carb or keto-diet will negatively affect either ‘female hormone balance’, menstrual cycles, or ovulation. It is claimed that there is a minimum amount of carbohydrate (i.e. 200 g per day) required to preserve hormone status and ovulation, along with other indicators of hormonal health. Does This Claim Stack Up? There is no evidence that 200 g per day is required to preserve markers of female hormone balance. In fact, the most commonly cited study to support the idea that there is a minimum requirement for carbohydrate showed no such thing. Read more and listen to the audio below
A recent article by vegan advocacy group PCRM has attacked using low-carb for veterans with diabetes. In this article, researcher Cliff Harvey provides a rebuttal to the PCRM arguments against LCHF for diabetes.
A recent study has been highly promoted in the media as another ‘nail in the coffin’ for red meat, suggesting increased risk of death from eating red meat. But was this effect really shown?
A Summary of Our Research: How did people ‘feel’ on a keto-diet? Very little research has been conducted on people’s subjective experiences of diet. The study of this is incredibly important because if we are to properly understand diet and prescribe, based on holistic effects, we need to know how people feel! Subjective perceptions of people on a keto-diet We analysed this in a qualitative study. We identified our participants subjective mood and experiences related to the ketogenic diet from daily diary entries and focus group findings. Read more & listen to the audio below
A summary of our research: Ketogenic supplements Low-carb diets and ketogenic diets are becoming increasingly popular for both lifestyle reasons and for the improvement of health and performance. However, there is little evidence for the superiority of keto- vs less restrictive low-carb approaches in the research. Greater carbohydrate restriction does provide additional benefits for some outcome measures like glucose, triglycerides (TG), and high-density lipoprotein cholesterol (HDL-c). There are also specific benefits from keto-diets and the levels of blood ketones they produce, including reduced inflammation, inhibited tumour growth (n some cancers), reduction in neurodegeneration, and increased metabolic flexibility. But, despite the benefits and popularity of keto, there is surprisingly little consensus in the published research on what nutritional ketosis (NK) actually is! There is also a complete lack of research on the time taken to achieve the common benchmark of nutritional ketosis ( ≥ 0.5 mmol/L beta-hydroxybutyrate (BOHB)) and on the symptoms of carbohydrate-withdrawal commonly described in mainstream media as ‘keto-flu’. Dietary supplements and methods to improve ketonaemia (blood ketone levels), time-to-NK, and symptoms of carbohydrate withdrawal and mood during keto-induction are similarly not well understood. Throughout my masters and doctoral research, my team and I provided, for the first time, a synthesis of research related to the time it takes for people to achieve ketosis and highlighted that there were no studies that had specifically evaluated adverse effects specifically during keto-induction. Read more & listen to the audio below
Issue 1 | Volume 1 | June 2019 In this issue: Keto-Flu, Ketogenesis, And Carb-Tolerance… A summary of our researchResearch commentary:Does fasting make you dumb? Two days of calorie deprivation impairs high level cognitive processes, mood, and self-reported exertion during aerobic exercise: A randomized double-blind, placebo-controlled studyIt’s about the food, stupid: Ultra-Processed Diets Cause Excess Calorie Intake and Weight Gain: An Inpatient Randomized Controlled Trial of Ad Libitum Food Intake Will eating just one extra slice of bacon really increase my cancer risk? Diet and colorectal cancer in UK Biobank: a prospective studyCan low-carbers use supplemental carbs during training? Exercising with low muscle glycogen content increases fat oxidation and decreases endogenous, but not exogenous carbohydrate oxidation Download the review below: