lIMIT INTAKE OF FOODS CONTAINING SATuRATED FAT, ADDED SAlT, ADDED SuGARS AND AlCOHOl
83Guideline 3
3.4.3 How limiting intake of alcohol may improve health outcomes
Alcohol begins to affect the brain within 5 minutes of consumption, with blood alcohol concentration peaking after
30–45 minutes. It takes approximately 1 hour for the liver to clear the alcohol from one standard drink from the
body, although this time varies depending upon liver size, lean body mass, individual alcohol tolerance and genes
controlling the expression of alcohol-metabolising enzymes in the liver.844-846 Because the rate of metabolism is
fixed, rapid consumption of multiple drinks results in a higher blood alcohol concentration.^794
Young adults who drink heavily tend to have smaller prefrontal cortices and white matter, structural abnormalities
of white matter and reduced hippocampal volumes.847,848 These structural changes lead to a diminished ability to
retrieve verbal and non-verbal material and poorer performance in attention-based tests.^836
The loss of brain tissue that occurs in people with chronic alcoholism seems to occur independently of Wernicke’s
encephalopathy and may be related to ethanol toxicity and poor nutrition.
• Cardiovascular effects: The effect of alcohol on the cardiovascular system is complex. Alcohol can raise blood
pressure and increase the risk of arrhythmias, shortness of breath, some types of cardiac failure, haemorrhagic
stroke and other circulatory problems. However, low levels of alcohol raise HDl cholesterol and reduce
accumulation of plaque in arteries.810,849 Alcohol can also have a mild anticoagulant effect.
• Diabetes: Alcohol affects the management of type 1 and type 2 diabetes through its effects on diet and
control of blood glucose levels. Alcohol interferes with the action of insulin, insulin secretagogues and
glucagon, thereby increasing the risk of hypoglycaemia in people with type I or 2 diabetes who take these
medications.850,851
• Dementia: The suggested protective relationship between alcohol and dementia may relate to the effect of
alcohol on blood lipids as one of the causal factors of dementia is microvascular changes within the brain.852,853
3.4.4 Practical considerations: limit intake of alcohol
Of Australians aged over 14 years, 83% reported having consumed alcohol at least once in the 12 months
preceding the 2007 National Drug Strategy Household Survey, with 8% drinking alcohol on a daily basis and
about 47% consuming alcohol at least weekly.^854 The majority of Australians who reported consuming alcohol
also reported moderating their intake, primarily to reduce the risk to their health. Methods included counting
and limiting the number of drinks, eating food while consuming alcohol, alternating between alcoholic and
non-alcoholic drinks and drinking low-alcohol drinks.^854
Nearly all alcohol is consumed as drinks, principally beers, wines, spirits and ciders. Alcoholic drinks contain few
other nutrients except for the bioactive flavonoids found in wine (mainly red wine). Alcoholic drinks are usually
consumed with foods, either as part of a meal or accompanied by snack foods, increasing the associated energy
intake. Some alcoholic drinks are mixed with additives including stimulants, sugars and other flavours.
The apparent average consumption of alcohol is estimated at 10.08 l per person over 15 years old per year,^855
and declines with age.^856 Consumption is 45% higher in the Northern Territory than in the rest of Australia.
The average consumption equates to an additional 650 kJ/day for every person over 15 years of age from alcohol.
Alcoholic drinks that contain added sugar have even more energy. If alcohol is consumed in addition to the normal
diet, leading to excess energy intake compared to requirements, weight will increase.
A full stomach reduces the rate of absorption of alcohol into the bloodstream. Drinking alcohol in combination
with eating therefore reduces the rate at which blood alcohol content increases. Drinking coffee, having a cold
shower, vomiting or exercising do not reduce blood alcohol content.^794
Pregnant and breastfeeding women
Alcohol consumption by pregnant women may harm the unborn baby. Heavy daily drinking or heavy episodes of
drinking have the most risk, and the risk from low-level drinking (one or two drinks per week) is likely to be small.
However there is no lower limit that can be guaranteed to be completely safe, so avoiding alcohol while pregnant
is the safest option.^794
There is limited evidence from human research on the effects of maternal alcohol consumption during lactation
and infant development. In Australia, it is suggested that mothers who do consume alcohol are more likely to
stop breastfeeding before six months compared to mothers who do not drink.857,858 Animal and observational