Broccoli, vinegar, and lemon juice are being tested to lower the glycemic index of white potatoes.
White potatoes have a high glycemic index, and consumption of foods with a high glycemic index can increase the risk of diabetes. Generally, after a meal, we would like our blood sugar to rise and fall slowly and naturally. But with high glycemic foods like potatoes, we get an exaggerated blood sugar spike. This leads our bodies to overcompensate with insulin, which forces our blood sugar to drop below when we started, leading to negative metabolic effects, such as an increase in triglycerides in the blood, as you can see below and at 0:34 in my video. How to Reduce the Glycemic Impact of Potatoes.
However, potatoes are a good source of vitamin C, potassium, and polyphenols, which may moderate their glycemic impact. This may explain why potatoes appear to have a neutral effect when it comes to lifespan, unlike other plant foods that have been actively associated with longevity.
In my last blog, I explained how the act of cooling cooked potatoes can lower their glycemic index, even if you reheat them in the microwave. How can we reduce the glycemic impact of white potatoes? The same way you improve anything in your nutritional life—add broccoli. Eating two servings of cooked broccoli with your mashed potatoes can, immediately, reduce your insulin needs by about 40%. Conversely, adding chicken breast makes things worse, and adding tuna fish makes things even worse, almost doubling the amount of insulin your body has to produce, as shown below and at 1:31 in mine. video.
Why do plant proteins make things better, but animal proteins make things worse? Because reduced consumption of branched-chain amino acids improves metabolic health. I put this in my book How not to eatand me too video by topic.
Talking about it How not to eatremember the section on vinegar? The graph below shows the blood sugar and insulin spikes a person with diabetes may experience after eating a bagel. If that same bagel is eaten with a tablespoon or so of apple cider vinegar diluted in about a quarter cup of water, however, the spikes are greatly reduced, as you can see below and at 2:10 for me video.
Does it work on potatoes, too? Just chilling potatoes can reduce blood sugar levels and insulin spikes, but to get the biggest drop in both, you should add a tablespoon of vinegar to reduce levels by 30% to 40%. And that was just pure white vinegar.
Is it the vinegar itself, or is there an acidic condiment that would do it? In a test tube, lemon juice appears to have a significant anti-starch effect, but you won’t know if it works in humans until you test it. And indeed, lemon juice lowers the glycemic response of bread. And not just a little, but about 30%, as you can see below and at 2:50 for me video.
Now, the study participants were drinking half a cup of lemon juice, but that makes it even more remarkable that it was beneficial because that added half a teaspoon of sugar, yet they still had a better blood sugar response. However, vinegar is very strong. One or two tablespoons a day of vinegar diluted in water can greatly improve short-term and long-term blood sugar control in people with diabetes, which is why doctors may want to include the use of vinegar as part of their dietary recommendations for their diabetic patients.
Doctor’s Note
This is the fourth video in a five-part series on potatoes. Missed the first three? See:
What about glycoalkaloid toxicity in potatoes? I cover that and discuss the best type of potatoes in my final upcoming video in the series: The Healthiest Kind of Potato.
