His chronicle of his trip, The naturalist on the River Amazons, became a bestseller when it was published in 1863.
Hot flashes and nausea are most commonly caused by hormonal imbalances in the body, most notably, by sex hormones. For women, a decrease in estrogen is often to blame, whereas in men, testosterone deficiency can create the problem. Sometimes, the symptoms occur for reasons not related to those hormones at all.
Some of the most common ones include: 1  Thyroid problems, such as hyperthyroidism, which causes an overabundance of thyroid hormone, can increase the bodyâs metabolism and lead to hot flashes and sweating. 2  Food and drink, including spicy foods, caffeine, and alcohol, can trigger hot flashes.