The research I am citing today was published in the Journal of Nutrition on August 1st, 2017. The study included 48 men and women with elevated LDL-cholesterol (the bad cholesterol that narrows arteries leading to heart attack and stroke). The intention was to compare the impact on LDL-cholesterol and HDL(the good cholesterol) of consuming either a handful of almonds per day versus a banana muffin a day. The diets were identical except for the daily snack.
Did almond improve HDL (the good cholesterol) levels?
On the almond diet, participants ingested about a handful of almonds per day. During the control period, they received a banana muffin instead. Subjects ingested a banana muffin each day for six weeks, then ingested a handful of almonds per day for six weeks.
The researchers found that while participants were on the almond diet, their HDL(the good cholesterol) levels and functionality improved. There’s a lot of research showing that a diet that includes almonds per day lowers the bad cholesterol (LDL-cholesterol), but the effect on the good cholesterol (HDL-cholesterol) has not been studied to the same extent.
In the normal weight subjects, the HDL-cholesterol increased quite substantially, as did HDL function.
How high levels of HDL cholesterol benefits our heart ?
HDL-cholesterol acts like a vacuum cleaner picking up some of the cholesterol that has already been deposited in the artery wall and transports it back to the liver. This function of HDL helps to reverse atherosclerosis, or artery narrowing, thereby reducing the risk of heart attack and stroke.
So, the higher your HDL(the good cholesterol) and the lower your LDL-cholesterol, the better is your risk profile for heart and cardiovascular disease. As HDL picks up cholesterol in the artery wall, it becomes larger, like a garbage bag slowly filling up with garbage.
It then takes the garbage (cholesterol in this case) back to the liver where it can be metabolized and eliminated from the body. It’s important to note that only normal weight subjects saw a rise in HDL and improvement in HDL function.
Overweight subjects did not see this benefit even when consuming the almonds. We have known for a while that being over weight decreases the synthesis and release of HDL from the liver and that losing excess body fat tends to increase HDL levels. So, this study showed that almonds can’t overcome the depressed HDL levels seen in overweight subjects.
Does exercise improve the HDL level in our body?
The other way to increase HDL(the good cholesterol) levels is to perform aerobic exercise regularly, which also helps to burn excess body fat and help achieve an ideal weight. So, aerobic exercise is a win-win with respect to increasing HDL levels.
In the meantime, I often see individuals who are at their ideal weight, and who also exercise, and yet their HDL level is not high enough to be considered ideal.
So, the addition of a handful of almonds to the daily diet may help to give HDL(the good cholesterol) a boost in these cases. As well, eating a handful of almonds per day instead of a muffin will also help individuals lose extra body fat over time. And once they do, the almonds will likely help them further raise their HDL levels – a very desirable outcome.
What is the ideal HDL blood level?
Men: above 1.17 mmol/L (45 mg/dL)
Women: above 1.42 mmol/L (55 mg/dL) – women tend to have slightly higher HDL levels.
Remember that previous studies have shown the walnuts are also helpful in preventing heart disease. So, a combination of almonds and walnuts might be the combination to consider in my view.
I’ve included a link to the research in the text below.
Reference:
- Berryman CE, Fleming JA, Kriss-Etherton PM. Inclusion of almonds in a cholesterol-lowering diet improves plasma HDL subspecies and cholesterol efflux to serum in normal-weight individuals with elevated LDL cholesterol. Journal of Nutrition. August 1, 2017. Vol 147, No 8:1517-1523?
- Almonds may help boost cholesterol clean-up crew: Eating almonds regularly may help improve HDL cholesterol levels, functionality